211211211220021 has 8 divisors (see below), whose sum is σ = 211236147267200. Its totient is φ = 211186275835680.

The previous prime is 211211211219991. The next prime is 211211211220091. The reversal of 211211211220021 is 120022112112112.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 211211211220021 - 2⁹ = 211211211219509 is a prime.

It is a super-2 number, since 2×211211211220021² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211211211220091) 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, 940405825 + ... + 940630393.

It is an arithmetic number, because the mean of its divisors is an integer number (26404518408400).

Almost surely, 2^{211211211220021} is an apocalyptic number.

It is an amenable number.

211211211220021 is a deficient number, since it is larger than the sum of its proper divisors (24936047179).

211211211220021 is an equidigital number, since it uses as much as digits as its factorization.

211211211220021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 331419.

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 211211211220021 its reverse (120022112112112), we get a palindrome (331233323332133).

The spelling of 211211211220021 in words is "two hundred eleven trillion, two hundred eleven billion, two hundred eleven million, two hundred twenty thousand, twenty-one".