31939090 has 16 divisors (see below), whose sum is σ = 60872472. Its totient is φ = 12024064.

The previous prime is 31939069. The next prime is 31939091. The reversal of 31939090 is 9093913.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 31911201 + 27889 = 5649^2 + 167^2 .

It is a Harshad number since it is a multiple of its sum of digits (34).

It is not an unprimeable number, because it can be changed into a prime (31939091) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 93769 + ... + 94108.

Almost surely, 2^31939090 is an apocalyptic number.

31939090 is a deficient number, since it is larger than the sum of its proper divisors (28933382).

31939090 is a wasteful number, since it uses less digits than its factorization.

31939090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 187901.

The product of its (nonzero) digits is 6561, while the sum is 34.

The square root of 31939090 is about 5651.4679508956. The cubic root of 31939090 is about 317.2786478729.

The spelling of 31939090 in words is "thirty-one million, nine hundred thirty-nine thousand, ninety".