21402179810001 has 45 divisors (see below), whose sum is σ = 31518411453529. Its totient is φ = 13994625284952.

The previous prime is 21402179809949. The next prime is 21402179810021. The reversal of 21402179810001 is 10001897120412.

The square root of 21402179810001 is 4626249.

It is a perfect power (a square), and thus also a powerful number.

21402179810001 is a `hidden beast` number, since 2 + 1 + 402 + 179 + 81 + 0 + 0 + 0 + 1 = 666.

It is not a de Polignac number, because 21402179810001 - 2²¹ = 21402177712849 is a prime.

It is a super-2 number, since 2×21402179810001² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21402179810021) 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 44 ways as a sum of consecutive naturals, for example, 48311918086 + ... + 48311918528.

Almost surely, 2^{21402179810001} is an apocalyptic number.

21402179810001 is the 4626249-th square number.

21402179810001 is the 2313125-th centered octagonal number.

It is an amenable number.

21402179810001 is a deficient number, since it is larger than the sum of its proper divisors (10116231643528).

21402179810001 is an frugal number, since it uses more digits than its factorization.

21402179810001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1128 (or 505 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 36.

Multiplying 21402179810001 by its sum of digits (36), we get a square (770478473160036 = 27757494²).

The spelling of 21402179810001 in words is "twenty-one trillion, four hundred two billion, one hundred seventy-nine million, eight hundred ten thousand, one".