31964640 has 48 divisors (see below), whose sum is σ = 100690128. Its totient is φ = 8523776.

The previous prime is 31964623. The next prime is 31964651. The reversal of 31964640 is 4646913.

It is a tau number, because it is divible by the number of its divisors (48).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32817 + ... + 33776.

It is an arithmetic number, because the mean of its divisors is an integer number (2097711).

Almost surely, 2^31964640 is an apocalyptic number.

31964640 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

31964640 is an abundant number, since it is smaller than the sum of its proper divisors (68725488).

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

31964640 is a wasteful number, since it uses less digits than its factorization.

31964640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66611 (or 66603 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 33.

The square root of 31964640 is about 5653.7279736471. The cubic root of 31964640 is about 317.3632287507.

The spelling of 31964640 in words is "thirty-one million, nine hundred sixty-four thousand, six hundred forty".