Search a number
-
+
31131013 = 41759293
BaseRepresentation
bin111011011000…
…0010110000101
32011120121201111
41312300112011
530432143023
63031125021
7525415654
oct166602605
964517644
1031131013
1116633211
12a513771
1365aca24
1441c519b
152aee00d
hex1db0585

31131013 has 4 divisors (see below), whose sum is σ = 31890348. Its totient is φ = 30371680.

The previous prime is 31130993. The next prime is 31131031. The reversal of 31131013 is 31013113.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 31013113 = 311000423.

It can be written as a sum of positive squares in 2 ways, for example, as 12623809 + 18507204 = 3553^2 + 4302^2 .

It is a cyclic number.

It is not a de Polignac number, because 31131013 - 221 = 29033861 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31130984 and 31131002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31131053) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 379606 + ... + 379687.

It is an arithmetic number, because the mean of its divisors is an integer number (7972587).

Almost surely, 231131013 is an apocalyptic number.

It is an amenable number.

31131013 is a deficient number, since it is larger than the sum of its proper divisors (759335).

31131013 is an equidigital number, since it uses as much as digits as its factorization.

31131013 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 759334.

The product of its (nonzero) digits is 27, while the sum is 13.

The square root of 31131013 is about 5579.5172730264. The cubic root of 31131013 is about 314.5799827409.

Adding to 31131013 its reverse (31013113), we get a palindrome (62144126).

It can be divided in two parts, 31 and 131013, that added together give a square (131044 = 3622).

The spelling of 31131013 in words is "thirty-one million, one hundred thirty-one thousand, thirteen".

Divisors: 1 41 759293 31131013