21551425541212 has 12 divisors (see below), whose sum is σ = 43102851082480. Its totient is φ = 9236325231936.

The previous prime is 21551425541183. The next prime is 21551425541227. The reversal of 21551425541212 is 21214552415512.

21551425541212 is an admirable number.

It is a super-2 number, since 2×21551425541212² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 384846884637 + ... + 384846884692.

Almost surely, 2^{21551425541212} is an apocalyptic number.

It is an amenable number.

21551425541212 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21551425541212 is a wasteful number, since it uses less digits than its factorization.

21551425541212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 769693769340 (or 769693769338 counting only the distinct ones).

The product of its digits is 160000, while the sum is 40.

Adding to 21551425541212 its reverse (21214552415512), we get a palindrome (42765977956724).

The spelling of 21551425541212 in words is "twenty-one trillion, five hundred fifty-one billion, four hundred twenty-five million, five hundred forty-one thousand, two hundred twelve".