61605016616 has 128 divisors (see below), whose sum is σ = 138801600000. Its totient is φ = 25263240960.

The previous prime is 61605016607. The next prime is 61605016657. The reversal of 61605016616 is 61661050616.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 61605016616.

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, 12079235 + ... + 12084333.

It is an arithmetic number, because the mean of its divisors is an integer number (1084387500).

Almost surely, 2^61605016616 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 61605016616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (69400800000).

61605016616 is an abundant number, since it is smaller than the sum of its proper divisors (77196583384).

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

61605016616 is a wasteful number, since it uses less digits than its factorization.

61605016616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5367 (or 5363 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 38.

The spelling of 61605016616 in words is "sixty-one billion, six hundred five million, sixteen thousand, six hundred sixteen".