6561602138 has 16 divisors (see below), whose sum is σ = 12113727360. Its totient is φ = 2595798576.

The previous prime is 6561602129. The next prime is 6561602141. The reversal of 6561602138 is 8312061656.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18026198 + ... + 18026561.

It is an arithmetic number, because the mean of its divisors is an integer number (757107960).

Almost surely, 2^6561602138 is an apocalyptic number.

6561602138 is a deficient number, since it is larger than the sum of its proper divisors (5552125222).

6561602138 is a wasteful number, since it uses less digits than its factorization.

6561602138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36052781.

The product of its (nonzero) digits is 51840, while the sum is 38.

The square root of 6561602138 is about 81003.7168159585. The cubic root of 6561602138 is about 1872.1327091143.

The spelling of 6561602138 in words is "six billion, five hundred sixty-one million, six hundred two thousand, one hundred thirty-eight".