20561551162 has 8 divisors (see below), whose sum is σ = 30921614100. Its totient is φ = 10254346464.

The previous prime is 20561551139. The next prime is 20561551193. The reversal of 20561551162 is 26115516502.

It can be written as a sum of positive squares in 2 ways, for example, as 20552376321 + 9174841 = 143361^2 + 3029^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13213587 + ... + 13215142.

Almost surely, 2^20561551162 is an apocalyptic number.

20561551162 is a deficient number, since it is larger than the sum of its proper divisors (10360062938).

20561551162 is a wasteful number, since it uses less digits than its factorization.

20561551162 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26429120.

The product of its (nonzero) digits is 18000, while the sum is 34.

The spelling of 20561551162 in words is "twenty billion, five hundred sixty-one million, five hundred fifty-one thousand, one hundred sixty-two".