661501896 has 64 divisors (see below), whose sum is σ = 1882552320. Its totient is φ = 191737920.

The previous prime is 661501871. The next prime is 661501931. The reversal of 661501896 is 698105166.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 48400 + ... + 60543.

It is an arithmetic number, because the mean of its divisors is an integer number (29414880).

Almost surely, 2^661501896 is an apocalyptic number.

661501896 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is an amenable number.

661501896 is an abundant number, since it is smaller than the sum of its proper divisors (1221050424).

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

661501896 is a wasteful number, since it uses less digits than its factorization.

661501896 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108986 (or 108982 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 42.

The square root of 661501896 is about 25719.6791581855. The cubic root of 661501896 is about 871.3186924947.

The spelling of 661501896 in words is "six hundred sixty-one million, five hundred one thousand, eight hundred ninety-six".