31791009 has 16 divisors (see below), whose sum is σ = 44755200. Its totient is φ = 20017296.

The previous prime is 31790981. The next prime is 31791059. The reversal of 31791009 is 90019713.

It is not a de Polignac number, because 31791009 - 2⁵ = 31790977 is a prime.

It is not an unprimeable number, because it can be changed into a prime (31791059) 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 15 ways as a sum of consecutive naturals, for example, 24622 + ... + 25880.

It is an arithmetic number, because the mean of its divisors is an integer number (2797200).

Almost surely, 2^31791009 is an apocalyptic number.

It is an amenable number.

31791009 is a deficient number, since it is larger than the sum of its proper divisors (12964191).

31791009 is a wasteful number, since it uses less digits than its factorization.

31791009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1724.

The product of its (nonzero) digits is 1701, while the sum is 30.

The square root of 31791009 is about 5638.3516208197. The cubic root of 31791009 is about 316.7875491708.

The spelling of 31791009 in words is "thirty-one million, seven hundred ninety-one thousand, nine".