31228660 has 48 divisors (see below), whose sum is σ = 70788816. Its totient is φ = 11528192.

The previous prime is 31228657. The next prime is 31228663. The reversal of 31228660 is 6682213.

It is an interprime number because it is at equal distance from previous prime (31228657) and next prime (31228663).

It can be written as a sum of positive squares in 8 ways, for example, as 824464 + 30404196 = 908^2 + 5514^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31228663) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 17154 + ... + 18886.

It is an arithmetic number, because the mean of its divisors is an integer number (1474767).

Almost surely, 2^31228660 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31228660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35394408).

31228660 is an abundant number, since it is smaller than the sum of its proper divisors (39560156).

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

31228660 is a wasteful number, since it uses less digits than its factorization.

31228660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1812 (or 1810 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 28.

The square root of 31228660 is about 5588.2609101580. The cubic root of 31228660 is about 314.9085482400.

The spelling of 31228660 in words is "thirty-one million, two hundred twenty-eight thousand, six hundred sixty".