21622255666542 has 24 divisors (see below), whose sum is σ = 48583339893816. Its totient is φ = 7207418555352.

The previous prime is 21622255666513. The next prime is 21622255666547. The reversal of 21622255666542 is 24566655222612.

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 (21622255666547) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 22245118513 + ... + 22245119484.

It is an arithmetic number, because the mean of its divisors is an integer number (2024305828909).

Almost surely, 2^{21622255666542} is an apocalyptic number.

21622255666542 is an abundant number, since it is smaller than the sum of its proper divisors (26961084227274).

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

21622255666542 is an equidigital number, since it uses as much as digits as its factorization.

21622255666542 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44490238014 (or 44490238002 counting only the distinct ones).

The product of its digits is 20736000, while the sum is 54.

The spelling of 21622255666542 in words is "twenty-one trillion, six hundred twenty-two billion, two hundred fifty-five million, six hundred sixty-six thousand, five hundred forty-two".