31213000 has 160 divisors (see below), whose sum is σ = 91760760. Its totient is φ = 9878400.

The previous prime is 31212899. The next prime is 31213009. The reversal of 31213000 is 31213.

It can be written as a sum of positive squares in 4 ways, for example, as 4235364 + 26977636 = 2058^2 + 5194^2 .

It is a Harshad number since it is a multiple of its sum of digits (10).

It is not an unprimeable number, because it can be changed into a prime (31213009) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 2400994 + ... + 2401006.

Almost surely, 2^31213000 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31213000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45880380).

31213000 is an abundant number, since it is smaller than the sum of its proper divisors (60547760).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31213000 is an equidigital number, since it uses as much as digits as its factorization.

31213000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62 (or 27 counting only the distinct ones).

The product of its (nonzero) digits is 18, while the sum is 10.

The square root of 31213000 is about 5586.8595829858. The cubic root of 31213000 is about 314.8559011693.

Adding to 31213000 its reverse (31213), we get a palindrome (31244213).

31213000 divided by its reverse (31213) gives a cube (1000 = 10³).

The spelling of 31213000 in words is "thirty-one million, two hundred thirteen thousand".