21202620555 has 16 divisors (see below), whose sum is σ = 34253556480. Its totient is φ = 11198276448.

The previous prime is 21202620539. The next prime is 21202620559. The reversal of 21202620555 is 55502620212.

It is not a de Polignac number, because 21202620555 - 2⁴ = 21202620539 is a prime.

It is a super-2 number, since 2×21202620555² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21202620559) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6860145 + ... + 6863234.

It is an arithmetic number, because the mean of its divisors is an integer number (2140847280).

Almost surely, 2^21202620555 is an apocalyptic number.

21202620555 is a deficient number, since it is larger than the sum of its proper divisors (13050935925).

21202620555 is a wasteful number, since it uses less digits than its factorization.

21202620555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13723490.

The product of its (nonzero) digits is 12000, while the sum is 30.

The spelling of 21202620555 in words is "twenty-one billion, two hundred two million, six hundred twenty thousand, five hundred fifty-five".