31861040 has 40 divisors (see below), whose sum is σ = 74325600. Its totient is φ = 12701696.

The previous prime is 31861031. The next prime is 31861079. The reversal of 31861040 is 4016813.

It is a tau number, because it is divible by the number of its divisors (40).

It is a junction number, because it is equal to n+sod(n) for n = 31860997 and 31861015.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35477 + ... + 36363.

It is an arithmetic number, because the mean of its divisors is an integer number (1858140).

Almost surely, 2^31861040 is an apocalyptic number.

It is an amenable number.

31861040 is an abundant number, since it is smaller than the sum of its proper divisors (42464560).

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

31861040 is a wasteful number, since it uses less digits than its factorization.

31861040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1349 (or 1343 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 23.

The square root of 31861040 is about 5644.5584415435. The cubic root of 31861040 is about 317.0199909772.

Adding to 31861040 its reverse (4016813), we get a palindrome (35877853).

The spelling of 31861040 in words is "thirty-one million, eight hundred sixty-one thousand, forty".