21255435665622 has 64 divisors (see below), whose sum is σ = 48650706685440. Its totient is φ = 6873788145888.

The previous prime is 21255435665621. The next prime is 21255435665677. The reversal of 21255435665622 is 22656653455212.

21255435665622 is a `hidden beast` number, since 2 + 1 + 2 + 5 + 5 + 4 + 3 + 5 + 6 + 6 + 5 + 622 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21255435665621) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 14635738 + ... + 16022349.

It is an arithmetic number, because the mean of its divisors is an integer number (760167291960).

Almost surely, 2^{21255435665622} is an apocalyptic number.

21255435665622 is an abundant number, since it is smaller than the sum of its proper divisors (27395271019818).

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

21255435665622 is a wasteful number, since it uses less digits than its factorization.

21255435665622 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30658482 (or 30658476 counting only the distinct ones).

The product of its digits is 25920000, while the sum is 54.

The spelling of 21255435665622 in words is "twenty-one trillion, two hundred fifty-five billion, four hundred thirty-five million, six hundred sixty-five thousand, six hundred twenty-two".