21655556241601 has 24 divisors (see below), whose sum is σ = 22917480456480. Its totient is φ = 20406178824192.

The previous prime is 21655556241587. The next prime is 21655556241659. The reversal of 21655556241601 is 10614265555612.

It is not a de Polignac number, because 21655556241601 - 2⁹ = 21655556241089 is a prime.

It is a super-2 number, since 2×21655556241601² (a number of 27 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21655556242601) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1790153185 + ... + 1790165281.

It is an arithmetic number, because the mean of its divisors is an integer number (954895019020).

Almost surely, 2^{21655556241601} is an apocalyptic number.

It is an amenable number.

21655556241601 is a deficient number, since it is larger than the sum of its proper divisors (1261924214879).

21655556241601 is an equidigital number, since it uses as much as digits as its factorization.

21655556241601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13553 (or 12976 counting only the distinct ones).

The product of its (nonzero) digits is 2160000, while the sum is 49.

The spelling of 21655556241601 in words is "twenty-one trillion, six hundred fifty-five billion, five hundred fifty-six million, two hundred forty-one thousand, six hundred one".