21557224505 has 16 divisors (see below), whose sum is σ = 26416938240. Its totient is φ = 16881753408.

The previous prime is 21557224453. The next prime is 21557224517. The reversal of 21557224505 is 50542275512.

It is a cyclic number.

It is not a de Polignac number, because 21557224505 - 2¹⁶ = 21557158969 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23684 + ... + 208986.

It is an arithmetic number, because the mean of its divisors is an integer number (1651058640).

Almost surely, 2^21557224505 is an apocalyptic number.

It is an amenable number.

21557224505 is a deficient number, since it is larger than the sum of its proper divisors (4859713735).

21557224505 is a wasteful number, since it uses less digits than its factorization.

21557224505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 185800.

The product of its (nonzero) digits is 140000, while the sum is 38.

The spelling of 21557224505 in words is "twenty-one billion, five hundred fifty-seven million, two hundred twenty-four thousand, five hundred five".