21557275522 has 4 divisors (see below), whose sum is σ = 32335913286. Its totient is φ = 10778637760.

The previous prime is 21557275451. The next prime is 21557275559. The reversal of 21557275522 is 22557275512.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 21039212401 + 518063121 = 145049^2 + 22761^2 .

It is a super-2 number, since 2×21557275522² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5389318879 + ... + 5389318882.

Almost surely, 2^21557275522 is an apocalyptic number.

21557275522 is a deficient number, since it is larger than the sum of its proper divisors (10778637764).

21557275522 is a wasteful number, since it uses less digits than its factorization.

21557275522 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10778637763.

The product of its digits is 490000, while the sum is 43.

The spelling of 21557275522 in words is "twenty-one billion, five hundred fifty-seven million, two hundred seventy-five thousand, five hundred twenty-two".