31306989 has 32 divisors (see below), whose sum is σ = 49029120. Its totient is φ = 17402112.

The previous prime is 31306987. The next prime is 31306997. The reversal of 31306989 is 98960313.

It is not a de Polignac number, because 31306989 - 2¹ = 31306987 is a prime.

It is a super-2 number, since 2×31306989² = 1960255120492242, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31306987) 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 31 ways as a sum of consecutive naturals, for example, 187384 + ... + 187550.

It is an arithmetic number, because the mean of its divisors is an integer number (1532160).

Almost surely, 2^31306989 is an apocalyptic number.

It is an amenable number.

31306989 is a deficient number, since it is larger than the sum of its proper divisors (17722131).

31306989 is a wasteful number, since it uses less digits than its factorization.

31306989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 369.

The product of its (nonzero) digits is 34992, while the sum is 39.

The square root of 31306989 is about 5595.2648730869. The cubic root of 31306989 is about 315.1716172415.

The spelling of 31306989 in words is "thirty-one million, three hundred six thousand, nine hundred eighty-nine".