661500650 has 12 divisors (see below), whose sum is σ = 1230391302. Its totient is φ = 264600240.

The previous prime is 661500641. The next prime is 661500673. The reversal of 661500650 is 56005166.

It can be written as a sum of positive squares in 3 ways, for example, as 551733121 + 109767529 = 23489^2 + 10477^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6614957 + ... + 6615056.

Almost surely, 2^661500650 is an apocalyptic number.

661500650 is a deficient number, since it is larger than the sum of its proper divisors (568890652).

661500650 is a wasteful number, since it uses less digits than its factorization.

661500650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13230025 (or 13230020 counting only the distinct ones).

The product of its (nonzero) digits is 5400, while the sum is 29.

The square root of 661500650 is about 25719.6549354769. The cubic root of 661500650 is about 871.3181454245.

The spelling of 661500650 in words is "six hundred sixty-one million, five hundred thousand, six hundred fifty".