211220121021 has 64 divisors (see below), whose sum is σ = 370137169920. Its totient is φ = 104100837120.

The previous prime is 211220121001. The next prime is 211220121023. The reversal of 211220121021 is 120121022112.

It is not a de Polignac number, because 211220121021 - 2⁵ = 211220120989 is a prime.

It is a super-2 number, since 2×211220121021² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211220121023) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 184885 + ... + 675738.

It is an arithmetic number, because the mean of its divisors is an integer number (5783393280).

Almost surely, 2^211220121021 is an apocalyptic number.

211220121021 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

211220121021 is a deficient number, since it is larger than the sum of its proper divisors (158917048899).

211220121021 is a wasteful number, since it uses less digits than its factorization.

211220121021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 860706.

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

Adding to 211220121021 its reverse (120121022112), we get a palindrome (331341143133).

The spelling of 211220121021 in words is "two hundred eleven billion, two hundred twenty million, one hundred twenty-one thousand, twenty-one".