21055366161201 has 16 divisors (see below), whose sum is σ = 29704507135040. Its totient is φ = 13229223782400.

The previous prime is 21055366161197. The next prime is 21055366161251. The reversal of 21055366161201 is 10216166355012.

It is not a de Polignac number, because 21055366161201 - 2² = 21055366161197 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21055366161201.

It is not an unprimeable number, because it can be changed into a prime (21055366161251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 956964100 + ... + 956986101.

It is an arithmetic number, because the mean of its divisors is an integer number (1856531695940).

Almost surely, 2^{21055366161201} is an apocalyptic number.

It is an amenable number.

21055366161201 is a deficient number, since it is larger than the sum of its proper divisors (8649140973839).

21055366161201 is a wasteful number, since it uses less digits than its factorization.

21055366161201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1913950416.

The product of its (nonzero) digits is 64800, while the sum is 39.

The spelling of 21055366161201 in words is "twenty-one trillion, fifty-five billion, three hundred sixty-six million, one hundred sixty-one thousand, two hundred one".