31123322220 has 96 divisors (see below), whose sum is σ = 94522147776. Its totient is φ = 7620812800.

The previous prime is 31123322189. The next prime is 31123322239. The reversal of 31123322220 is 2222332113.

It is a happy number.

It is a super-2 number, since 2×31123322220² (a number of 22 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 330291 + ... + 413930.

It is an arithmetic number, because the mean of its divisors is an integer number (984605706).

Almost surely, 2^31123322220 is an apocalyptic number.

31123322220 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

31123322220 is an abundant number, since it is smaller than the sum of its proper divisors (63398825556).

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

31123322220 is a wasteful number, since it uses less digits than its factorization.

31123322220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 744291 (or 744289 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 21.

Adding to 31123322220 its reverse (2222332113), we get a palindrome (33345654333).

The spelling of 31123322220 in words is "thirty-one billion, one hundred twenty-three million, three hundred twenty-two thousand, two hundred twenty".