31221004 has 12 divisors (see below), whose sum is σ = 54676944. Its totient is φ = 15599024.

The previous prime is 31220989. The next prime is 31221017. The reversal of 31221004 is 40012213.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7089 + ... + 10615.

It is an arithmetic number, because the mean of its divisors is an integer number (4556412).

Almost surely, 2^31221004 is an apocalyptic number.

It is an amenable number.

31221004 is a deficient number, since it is larger than the sum of its proper divisors (23455940).

31221004 is a wasteful number, since it uses less digits than its factorization.

31221004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5744 (or 5742 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 31221004 is about 5587.5758607826. The cubic root of 31221004 is about 314.8828118716.

Adding to 31221004 its reverse (40012213), we get a palindrome (71233217).

It can be divided in two parts, 312 and 21004, that added together give a square (21316 = 146²).

The spelling of 31221004 in words is "thirty-one million, two hundred twenty-one thousand, four".