31392985 has 16 divisors (see below), whose sum is σ = 40832064. Its totient is φ = 23032512.

The previous prime is 31392973. The next prime is 31392989. The reversal of 31392985 is 58929313.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31392985 is a prime.

It is not an unprimeable number, because it can be changed into a prime (31392989) 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, 9114 + ... + 12076.

It is an arithmetic number, because the mean of its divisors is an integer number (2552004).

Almost surely, 2^31392985 is an apocalyptic number.

It is an amenable number.

31392985 is a deficient number, since it is larger than the sum of its proper divisors (9439079).

31392985 is a wasteful number, since it uses less digits than its factorization.

31392985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3144.

The product of its digits is 58320, while the sum is 40.

The square root of 31392985 is about 5602.9443152685. The cubic root of 31392985 is about 315.4599311349.

The spelling of 31392985 in words is "thirty-one million, three hundred ninety-two thousand, nine hundred eighty-five".