31306990 has 32 divisors (see below), whose sum is σ = 66207456. Its totient is φ = 10508160.

The previous prime is 31306987. The next prime is 31306997. The reversal of 31306990 is 9960313.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31306997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9517 + ... + 12376.

It is an arithmetic number, because the mean of its divisors is an integer number (2068983).

Almost surely, 2^31306990 is an apocalyptic number.

31306990 is an abundant number, since it is smaller than the sum of its proper divisors (34900466).

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

31306990 is a wasteful number, since it uses less digits than its factorization.

31306990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21924.

The product of its (nonzero) digits is 4374, while the sum is 31.

The square root of 31306990 is about 5595.2649624482. The cubic root of 31306990 is about 315.1716205972.

The spelling of 31306990 in words is "thirty-one million, three hundred six thousand, nine hundred ninety".