661550650 has 24 divisors (see below), whose sum is σ = 1231734780. Its totient is φ = 264351360.

The previous prime is 661550641. The next prime is 661550651. The reversal of 661550650 is 56055166.

It can be written as a sum of positive squares in 6 ways, for example, as 103693489 + 557857161 = 10183^2 + 23619^2 .

It is not an unprimeable number, because it can be changed into a prime (661550651) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 47262 + ... + 59638.

Almost surely, 2^661550650 is an apocalyptic number.

661550650 is a deficient number, since it is larger than the sum of its proper divisors (570184130).

661550650 is a wasteful number, since it uses less digits than its factorization.

661550650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13458 (or 13453 counting only the distinct ones).

The product of its (nonzero) digits is 27000, while the sum is 34.

The square root of 661550650 is about 25720.6269363715. The cubic root of 661550650 is about 871.3400979400.

The spelling of 661550650 in words is "six hundred sixty-one million, five hundred fifty thousand, six hundred fifty".