31304032040 has 64 divisors (see below), whose sum is σ = 72372767760. Its totient is φ = 12177285120.

The previous prime is 31304032037. The next prime is 31304032043. The reversal of 31304032040 is 4023040313.

It is an interprime number because it is at equal distance from previous prime (31304032037) and next prime (31304032043).

It can be written as a sum of positive squares in 8 ways, for example, as 15668530276 + 15635501764 = 125174^2 + 125042^2 .

It is a super-2 number, since 2×31304032040² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (31304032043) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4230584 + ... + 4237976.

Almost surely, 2^31304032040 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 31304032040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36186383880).

31304032040 is an abundant number, since it is smaller than the sum of its proper divisors (41068735720).

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

31304032040 is a wasteful number, since it uses less digits than its factorization.

31304032040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10302 (or 10298 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 20.

Adding to 31304032040 its reverse (4023040313), we get a palindrome (35327072353).

The spelling of 31304032040 in words is "thirty-one billion, three hundred four million, thirty-two thousand, forty".