31664623 has 4 divisors (see below), whose sum is σ = 31713768. Its totient is φ = 31615480.

The previous prime is 31664603. The next prime is 31664639. The reversal of 31664623 is 32646613.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31664623 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31664603) 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, 23593 + ... + 24898.

It is an arithmetic number, because the mean of its divisors is an integer number (7928442).

Almost surely, 2^31664623 is an apocalyptic number.

31664623 is a deficient number, since it is larger than the sum of its proper divisors (49145).

31664623 is an equidigital number, since it uses as much as digits as its factorization.

31664623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49144.

The product of its digits is 15552, while the sum is 31.

The square root of 31664623 is about 5627.1327512331. The cubic root of 31664623 is about 316.3671925283.

The spelling of 31664623 in words is "thirty-one million, six hundred sixty-four thousand, six hundred twenty-three".