21230747555 has 16 divisors (see below), whose sum is σ = 25643508384. Its totient is φ = 16873608960.

The previous prime is 21230747533. The next prime is 21230747567. The reversal of 21230747555 is 55574703212.

It is not a de Polignac number, because 21230747555 - 2¹² = 21230743459 is a prime.

It is a Duffinian number.

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, 3303245 + ... + 3309665.

It is an arithmetic number, because the mean of its divisors is an integer number (1602719274).

Almost surely, 2^21230747555 is an apocalyptic number.

21230747555 is a deficient number, since it is larger than the sum of its proper divisors (4412760829).

21230747555 is a wasteful number, since it uses less digits than its factorization.

21230747555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10646.

The product of its (nonzero) digits is 294000, while the sum is 41.

The spelling of 21230747555 in words is "twenty-one billion, two hundred thirty million, seven hundred forty-seven thousand, five hundred fifty-five".