31228290 has 48 divisors (see below), whose sum is σ = 81476928. Its totient is φ = 8298528.

The previous prime is 31228283. The next prime is 31228297. The reversal of 31228290 is 9282213.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (31228283) and next prime (31228297).

It is not an unprimeable number, because it can be changed into a prime (31228297) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 41659 + ... + 42401.

It is an arithmetic number, because the mean of its divisors is an integer number (1697436).

Almost surely, 2^31228290 is an apocalyptic number.

31228290 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

31228290 is an abundant number, since it is smaller than the sum of its proper divisors (50248638).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31228290 is a wasteful number, since it uses less digits than its factorization.

31228290 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1223 (or 1220 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 31228290 is about 5588.2278049485. The cubic root of 31228290 is about 314.9073045467.

The spelling of 31228290 in words is "thirty-one million, two hundred twenty-eight thousand, two hundred ninety".