31379985 has 96 divisors (see below), whose sum is σ = 68490240. Its totient is φ = 12939264.

The previous prime is 31379969. The next prime is 31380017. The reversal of 31379985 is 58997313.

It is a happy number.

It is not a de Polignac number, because 31379985 - 2⁴ = 31379969 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 31379985.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 323457 + ... + 323553.

It is an arithmetic number, because the mean of its divisors is an integer number (713440).

Almost surely, 2^31379985 is an apocalyptic number.

31379985 is a gapful number since it is divisible by the number (35) formed by its first and last digit.

It is an amenable number.

31379985 is an abundant number, since it is smaller than the sum of its proper divisors (37110255).

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

31379985 is a wasteful number, since it uses less digits than its factorization.

31379985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 207 (or 204 counting only the distinct ones).

The product of its digits is 204120, while the sum is 45.

The square root of 31379985 is about 5601.7840908054. The cubic root of 31379985 is about 315.4163805846.

The spelling of 31379985 in words is "thirty-one million, three hundred seventy-nine thousand, nine hundred eighty-five".