31890245 has 8 divisors (see below), whose sum is σ = 38647800. Its totient is φ = 25259200.

The previous prime is 31890233. The next prime is 31890281. The reversal of 31890245 is 54209813.

It can be written as a sum of positive squares in 4 ways, for example, as 6980164 + 24910081 = 2642^2 + 4991^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 31890245 - 2⁸ = 31889989 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31070 + ... + 32079.

It is an arithmetic number, because the mean of its divisors is an integer number (4830975).

Almost surely, 2^31890245 is an apocalyptic number.

It is an amenable number.

31890245 is a deficient number, since it is larger than the sum of its proper divisors (6757555).

31890245 is a wasteful number, since it uses less digits than its factorization.

31890245 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63255.

The product of its (nonzero) digits is 8640, while the sum is 32.

The square root of 31890245 is about 5647.1448538177. The cubic root of 31890245 is about 317.1168254535.

The spelling of 31890245 in words is "thirty-one million, eight hundred ninety thousand, two hundred forty-five".