31311690 has 16 divisors (see below), whose sum is σ = 75148128. Its totient is φ = 8349776.

The previous prime is 31311689. The next prime is 31311701. The reversal of 31311690 is 9611313.

It is a super-2 number, since 2×31311690² = 1960843861312200, which contains 22 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 31311690.

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, 521832 + ... + 521891.

It is an arithmetic number, because the mean of its divisors is an integer number (4696758).

Almost surely, 2^31311690 is an apocalyptic number.

31311690 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

31311690 is an abundant number, since it is smaller than the sum of its proper divisors (43836438).

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

31311690 is a wasteful number, since it uses less digits than its factorization.

31311690 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1043733.

The product of its (nonzero) digits is 486, while the sum is 24.

The square root of 31311690 is about 5595.6849446694. The cubic root of 31311690 is about 315.1873916491.

The spelling of 31311690 in words is "thirty-one million, three hundred eleven thousand, six hundred ninety".