21231420233212 has 24 divisors (see below), whose sum is σ = 43832609515520. Its totient is φ = 8805658160880.

The previous prime is 21231420233147. The next prime is 21231420233237. The reversal of 21231420233212 is 21233202413212.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a congruent number.

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, 12230079912 + ... + 12230081647.

Almost surely, 2^{21231420233212} is an apocalyptic number.

It is an amenable number.

21231420233212 is an abundant number, since it is smaller than the sum of its proper divisors (22601189282308).

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

21231420233212 is a wasteful number, since it uses less digits than its factorization.

21231420233212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24460161601 (or 24460161599 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 28.

Adding to 21231420233212 its reverse (21233202413212), we get a palindrome (42464622646424).

The spelling of 21231420233212 in words is "twenty-one trillion, two hundred thirty-one billion, four hundred twenty million, two hundred thirty-three thousand, two hundred twelve".