136620661561 has 16 divisors (see below), whose sum is σ = 138804277248. Its totient is φ = 134450758800.

The previous prime is 136620661553. The next prime is 136620661621. The reversal of 136620661561 is 165166026631.

It is a cyclic number.

It is not a de Polignac number, because 136620661561 - 2³ = 136620661553 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (136620661511) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 33230896 + ... + 33235006.

It is an arithmetic number, because the mean of its divisors is an integer number (8675267328).

Almost surely, 2^136620661561 is an apocalyptic number.

It is an amenable number.

136620661561 is a deficient number, since it is larger than the sum of its proper divisors (2183615687).

136620661561 is a wasteful number, since it uses less digits than its factorization.

136620661561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5652.

The product of its (nonzero) digits is 233280, while the sum is 43.

The spelling of 136620661561 in words is "one hundred thirty-six billion, six hundred twenty million, six hundred sixty-one thousand, five hundred sixty-one".