31309004 has 12 divisors (see below), whose sum is σ = 54880728. Its totient is φ = 15628800.

The previous prime is 31309001. The next prime is 31309007. The reversal of 31309004 is 40090313.

It is an interprime number because it is at equal distance from previous prime (31309001) and next prime (31309007).

It is a hoax number, since the sum of its digits (20) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (31309001) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3542 + ... + 8669.

It is an arithmetic number, because the mean of its divisors is an integer number (4573394).

Almost surely, 2^31309004 is an apocalyptic number.

It is an amenable number.

31309004 is a deficient number, since it is larger than the sum of its proper divisors (23571724).

31309004 is a wasteful number, since it uses less digits than its factorization.

31309004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12856 (or 12854 counting only the distinct ones).

The product of its (nonzero) digits is 324, while the sum is 20.

The square root of 31309004 is about 5595.4449331577. Note that the first 3 decimals coincide. The cubic root of 31309004 is about 315.1783788540.

Adding to 31309004 its reverse (40090313), we get a palindrome (71399317).

The spelling of 31309004 in words is "thirty-one million, three hundred nine thousand, four".