31643420 has 12 divisors (see below), whose sum is σ = 66451224. Its totient is φ = 12657360.

The previous prime is 31643419. The next prime is 31643429. The reversal of 31643420 is 2434613.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31643429) 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, 791066 + ... + 791105.

It is an arithmetic number, because the mean of its divisors is an integer number (5537602).

Almost surely, 2^31643420 is an apocalyptic number.

It is an amenable number.

31643420 is an abundant number, since it is smaller than the sum of its proper divisors (34807804).

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

31643420 is a wasteful number, since it uses less digits than its factorization.

31643420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1582180 (or 1582178 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 23.

The square root of 31643420 is about 5625.2484389581. The cubic root of 31643420 is about 316.2965623766.

The spelling of 31643420 in words is "thirty-one million, six hundred forty-three thousand, four hundred twenty".