21122102100021 has 8 divisors (see below), whose sum is σ = 30329172246240. Its totient is φ = 12998216676912.

The previous prime is 21122102100007. The next prime is 21122102100049. The reversal of 21122102100021 is 12000120122112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21122102100021 - 2¹⁴ = 21122102083637 is a prime.

It is a super-2 number, since 2×21122102100021² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21122102600021) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 270796180731 + ... + 270796180808.

It is an arithmetic number, because the mean of its divisors is an integer number (3791146530780).

Almost surely, 2^{21122102100021} is an apocalyptic number.

It is an amenable number.

21122102100021 is a deficient number, since it is larger than the sum of its proper divisors (9207070146219).

21122102100021 is a wasteful number, since it uses less digits than its factorization.

21122102100021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 541592361555.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21122102100021 its reverse (12000120122112), we get a palindrome (33122222222133).

The spelling of 21122102100021 in words is "twenty-one trillion, one hundred twenty-two billion, one hundred two million, one hundred thousand, twenty-one".