21121011122001 has 32 divisors (see below), whose sum is σ = 32206206059520. Its totient is φ = 12060972795456.

The previous prime is 21121011121961. The next prime is 21121011122087. The reversal of 21121011122001 is 10022111012112.

It is a happy number.

It is not a de Polignac number, because 21121011122001 - 2¹⁷ = 21121010990929 is a prime.

It is a super-2 number, since 2×21121011122001² (a number of 27 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21121011122501) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 372167710 + ... + 372224456.

It is an arithmetic number, because the mean of its divisors is an integer number (1006443939360).

Almost surely, 2^{21121011122001} is an apocalyptic number.

21121011122001 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21121011122001 is a deficient number, since it is larger than the sum of its proper divisors (11085194937519).

21121011122001 is a wasteful number, since it uses less digits than its factorization.

21121011122001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68453.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 21121011122001 its reverse (10022111012112), we get a palindrome (31143122134113).

It can be divided in two parts, 211210111 and 22001, that added together give a palindrome (211232112).

The spelling of 21121011122001 in words is "twenty-one trillion, one hundred twenty-one billion, eleven million, one hundred twenty-two thousand, one".