31140405 has 12 divisors (see below), whose sum is σ = 53976780. Its totient is φ = 16608192.

The previous prime is 31140401. The next prime is 31140407. The reversal of 31140405 is 50404113.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 7257636 + 23882769 = 2694^2 + 4887^2 .

It is not a de Polignac number, because 31140405 - 2² = 31140401 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31140401) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 345960 + ... + 346049.

It is an arithmetic number, because the mean of its divisors is an integer number (4498065).

Almost surely, 2^31140405 is an apocalyptic number.

It is an amenable number.

31140405 is a deficient number, since it is larger than the sum of its proper divisors (22836375).

31140405 is a wasteful number, since it uses less digits than its factorization.

31140405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 692020 (or 692017 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 31140405 is about 5580.3588594283. The cubic root of 31140405 is about 314.6116150570.

Adding to 31140405 its reverse (50404113), we get a palindrome (81544518).

The spelling of 31140405 in words is "thirty-one million, one hundred forty thousand, four hundred five".