31220180 has 24 divisors (see below), whose sum is σ = 66801672. Its totient is φ = 12252032.

The previous prime is 31220179. The next prime is 31220207. The reversal of 31220180 is 8102213.

It can be written as a sum of positive squares in 4 ways, for example, as 5373124 + 25847056 = 2318^2 + 5084^2 .

It is a congruent number.

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, 13667 + ... + 15786.

It is an arithmetic number, because the mean of its divisors is an integer number (2783403).

Almost surely, 2^31220180 is an apocalyptic number.

It is an amenable number.

31220180 is an abundant number, since it is smaller than the sum of its proper divisors (35581492).

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

31220180 is a wasteful number, since it uses less digits than its factorization.

31220180 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29515 (or 29513 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 31220180 is about 5587.5021252792. The cubic root of 31220180 is about 314.8800416668.

Adding to 31220180 its reverse (8102213), we get a palindrome (39322393).

The spelling of 31220180 in words is "thirty-one million, two hundred twenty thousand, one hundred eighty".