61555218576 has 160 divisors (see below), whose sum is σ = 166112760960. Its totient is φ = 19617841152.

The previous prime is 61555218563. The next prime is 61555218583. The reversal of 61555218576 is 67581255516.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 106681200 + ... + 106681776.

It is an arithmetic number, because the mean of its divisors is an integer number (1038204756).

Almost surely, 2^61555218576 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61555218576, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (83056380480).

61555218576 is an abundant number, since it is smaller than the sum of its proper divisors (104557542384).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

61555218576 is a wasteful number, since it uses less digits than its factorization.

61555218576 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1233 (or 1227 counting only the distinct ones).

The product of its digits is 2520000, while the sum is 51.

The spelling of 61555218576 in words is "sixty-one billion, five hundred fifty-five million, two hundred eighteen thousand, five hundred seventy-six".