21225772655 has 8 divisors (see below), whose sum is σ = 26349235200. Its totient is φ = 16395079456.

The previous prime is 21225772627. The next prime is 21225772661. The reversal of 21225772655 is 55627752212.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21225772655 - 2⁶ = 21225772591 is a prime.

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, 73192175 + ... + 73192464.

It is an arithmetic number, because the mean of its divisors is an integer number (3293654400).

Almost surely, 2^21225772655 is an apocalyptic number.

21225772655 is a deficient number, since it is larger than the sum of its proper divisors (5123462545).

21225772655 is a wasteful number, since it uses less digits than its factorization.

21225772655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 146384673.

The product of its digits is 588000, while the sum is 44.

The spelling of 21225772655 in words is "twenty-one billion, two hundred twenty-five million, seven hundred seventy-two thousand, six hundred fifty-five".