31890472 has 8 divisors (see below), whose sum is σ = 59794650. Its totient is φ = 15945232.

The previous prime is 31890407. The next prime is 31890473. The reversal of 31890472 is 27409813.

It can be written as a sum of positive squares in only one way, i.e., 30980356 + 910116 = 5566^2 + 954^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is not an unprimeable number, because it can be changed into a prime (31890473) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1993147 + ... + 1993162.

Almost surely, 2^31890472 is an apocalyptic number.

It is an amenable number.

31890472 is a deficient number, since it is larger than the sum of its proper divisors (27904178).

31890472 is a wasteful number, since it uses less digits than its factorization.

31890472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3986315 (or 3986311 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 31890472 is about 5647.1649524341. The cubic root of 31890472 is about 317.1175778816.

The spelling of 31890472 in words is "thirty-one million, eight hundred ninety thousand, four hundred seventy-two".