21100100012001 has 12 divisors (see below), whose sum is σ = 32082023410320. Its totient is φ = 13326378954840.

The previous prime is 21100100011961. The next prime is 21100100012003. The reversal of 21100100012001 is 10021000100112.

It is a happy number.

It is not a de Polignac number, because 21100100012001 - 2⁷ = 21100100011873 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is not an unprimeable number, because it can be changed into a prime (21100100012003) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 61696198695 + ... + 61696199036.

It is an arithmetic number, because the mean of its divisors is an integer number (2673501950860).

Almost surely, 2^{21100100012001} is an apocalyptic number.

It is an amenable number.

21100100012001 is a deficient number, since it is larger than the sum of its proper divisors (10981923398319).

21100100012001 is a wasteful number, since it uses less digits than its factorization.

21100100012001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123392397756 (or 123392397753 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 21100100012001 its reverse (10021000100112), we get a palindrome (31121100112113).

The spelling of 21100100012001 in words is "twenty-one trillion, one hundred billion, one hundred million, twelve thousand, one".