31242290 has 16 divisors (see below), whose sum is σ = 56339712. Its totient is φ = 12473904.

The previous prime is 31242247. The next prime is 31242307. The reversal of 31242290 is 9224213.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 3497 + ... + 8643.

It is an arithmetic number, because the mean of its divisors is an integer number (3521232).

Almost surely, 2^31242290 is an apocalyptic number.

31242290 is a deficient number, since it is larger than the sum of its proper divisors (25097422).

31242290 is a wasteful number, since it uses less digits than its factorization.

31242290 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5761.

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 31242290 is about 5589.4802978452. The cubic root of 31242290 is about 314.9543563663.

The spelling of 31242290 in words is "thirty-one million, two hundred forty-two thousand, two hundred ninety".