20312021111 has 4 divisors (see below), whose sum is σ = 20501853192. Its totient is φ = 20122189032.

The previous prime is 20312021083. The next prime is 20312021131. The reversal of 20312021111 is 11112021302.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20312021111 - 2²² = 20307826807 is a prime.

It is a super-2 number, since 2×20312021111² (a number of 21 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 (20312021131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 94915880 + ... + 94916093.

It is an arithmetic number, because the mean of its divisors is an integer number (5125463298).

Almost surely, 2^20312021111 is an apocalyptic number.

20312021111 is a deficient number, since it is larger than the sum of its proper divisors (189832081).

20312021111 is a wasteful number, since it uses less digits than its factorization.

20312021111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 189832080.

The product of its (nonzero) digits is 24, while the sum is 14.

Adding to 20312021111 its reverse (11112021302), we get a palindrome (31424042413).

The spelling of 20312021111 in words is "twenty billion, three hundred twelve million, twenty-one thousand, one hundred eleven".