661016916 has 192 divisors, whose sum is σ = 2183731200. Its totient is φ = 168334848.

The previous prime is 661016893. The next prime is 661016953. The reversal of 661016916 is 619610166.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 242835 + ... + 245541.

It is an arithmetic number, because the mean of its divisors is an integer number (11373600).

Almost surely, 2^661016916 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 661016916, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1091865600).

661016916 is an abundant number, since it is smaller than the sum of its proper divisors (1522714284).

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

661016916 is a wasteful number, since it uses less digits than its factorization.

661016916 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2763 (or 2755 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 36.

The square root of 661016916 is about 25710.2492403322. The cubic root of 661016916 is about 871.1057047196.

The spelling of 661016916 in words is "six hundred sixty-one million, sixteen thousand, nine hundred sixteen".