211311231021 has 48 divisors (see below), whose sum is σ = 367890906240. Its totient is φ = 115293404160.

The previous prime is 211311230761. The next prime is 211311231077. The reversal of 211311231021 is 120132113112.

211311231021 is a `hidden beast` number, since 21 + 1 + 311 + 2 + 310 + 21 = 666.

It is not a de Polignac number, because 211311231021 - 2¹⁵ = 211311198253 is a prime.

It is a super-2 number, since 2×211311231021² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 211311230985 and 211311231003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (211311231821) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2690776 + ... + 2768193.

It is an arithmetic number, because the mean of its divisors is an integer number (7664393880).

Almost surely, 2^211311231021 is an apocalyptic number.

It is an amenable number.

211311231021 is a deficient number, since it is larger than the sum of its proper divisors (156579675219).

211311231021 is a wasteful number, since it uses less digits than its factorization.

211311231021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5459026 (or 5459023 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

Adding to 211311231021 its reverse (120132113112), we get a palindrome (331443344133).

The spelling of 211311231021 in words is "two hundred eleven billion, three hundred eleven million, two hundred thirty-one thousand, twenty-one".