20930811181 has 4 divisors (see below), whose sum is σ = 23920927072. Its totient is φ = 17940695292.

The previous prime is 20930811173. The next prime is 20930811191. The reversal of 20930811181 is 18111803902.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20930811181 - 2³ = 20930811173 is a prime.

It is a super-2 number, since 2×20930811181² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20930811131) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1495057935 + ... + 1495057948.

It is an arithmetic number, because the mean of its divisors is an integer number (5980231768).

Almost surely, 2^20930811181 is an apocalyptic number.

It is an amenable number.

20930811181 is a deficient number, since it is larger than the sum of its proper divisors (2990115891).

20930811181 is an equidigital number, since it uses as much as digits as its factorization.

20930811181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2990115890.

The product of its (nonzero) digits is 3456, while the sum is 34.

The spelling of 20930811181 in words is "twenty billion, nine hundred thirty million, eight hundred eleven thousand, one hundred eighty-one".