61291915776 has 960 divisors, whose sum is σ = 235339104000. Its totient is φ = 15216574464.

The previous prime is 61291915759. The next prime is 61291915807. The reversal of 61291915776 is 67751919216.

61291915776 is a `hidden beast` number, since 61 + 2 + 9 + 1 + 9 + 1 + 577 + 6 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 390394290 + ... + 390394446.

It is an arithmetic number, because the mean of its divisors is an integer number (245144900).

Almost surely, 2^61291915776 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 61291915776, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (117669552000).

61291915776 is an abundant number, since it is smaller than the sum of its proper divisors (174047188224).

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

61291915776 is a wasteful number, since it uses less digits than its factorization.

61291915776 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 234 (or 201 counting only the distinct ones).

The product of its digits is 1428840, while the sum is 54.

The spelling of 61291915776 in words is "sixty-one billion, two hundred ninety-one million, nine hundred fifteen thousand, seven hundred seventy-six".