221031012 has 36 divisors (see below), whose sum is σ = 539152880. Its totient is φ = 70471632.

The previous prime is 221031001. The next prime is 221031017. The reversal of 221031012 is 210130122.

221031012 = 3089² + 3090² + ... + 3111².

It is a Harshad number since it is a multiple of its sum of digits (12).

It is not an unprimeable number, because it can be changed into a prime (221031017) 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 11 ways as a sum of consecutive naturals, for example, 11062 + ... + 23757.

Almost surely, 2^221031012 is an apocalyptic number.

It is an amenable number.

221031012 is an abundant number, since it is smaller than the sum of its proper divisors (318121868).

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

221031012 is a wasteful number, since it uses less digits than its factorization.

221031012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34872 (or 34847 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 221031012 is about 14867.1117571639. Note that the first 3 decimals coincide. The cubic root of 221031012 is about 604.6226383393.

Adding to 221031012 its reverse (210130122), we get a palindrome (431161134).

The spelling of 221031012 in words is "two hundred twenty-one million, thirty-one thousand, twelve".