20651051161 has 6 divisors (see below), whose sum is σ = 22361789310. Its totient is φ = 19062508608.

The previous prime is 20651051159. The next prime is 20651051173. The reversal of 20651051161 is 16115015602.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 872847936 + 19778203225 = 29544^2 + 140635^2 .

It is not a de Polignac number, because 20651051161 - 2¹ = 20651051159 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20651031161) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 61097616 + ... + 61097953.

It is an arithmetic number, because the mean of its divisors is an integer number (3726964885).

Almost surely, 2^20651051161 is an apocalyptic number.

It is an amenable number.

20651051161 is a deficient number, since it is larger than the sum of its proper divisors (1710738149).

20651051161 is a wasteful number, since it uses less digits than its factorization.

20651051161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122195595 (or 122195582 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 28.

Adding to 20651051161 its reverse (16115015602), we get a palindrome (36766066763).

The spelling of 20651051161 in words is "twenty billion, six hundred fifty-one million, fifty-one thousand, one hundred sixty-one".