21213644631212 has 24 divisors (see below), whose sum is σ = 40585497301440. Its totient is φ = 9621917839760.

The previous prime is 21213644631209. The next prime is 21213644631331.

21213644631212 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×21213644631212² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 516176762 + ... + 516217857.

It is an arithmetic number, because the mean of its divisors is an integer number (1691062387560).

Almost surely, 2^{21213644631212} is an apocalyptic number.

21213644631212 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21213644631212 is a deficient number, since it is larger than the sum of its proper divisors (19371852670228).

21213644631212 is a wasteful number, since it uses less digits than its factorization.

21213644631212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1032395101 (or 1032395099 counting only the distinct ones).

The product of its digits is 82944, while the sum is 38.

It can be divided in two parts, 2121364 and 4631212, that added together give a palindrome (6752576).

The spelling of 21213644631212 in words is "twenty-one trillion, two hundred thirteen billion, six hundred forty-four million, six hundred thirty-one thousand, two hundred twelve".