661100650 has 72 divisors (see below), whose sum is σ = 1440684576. Its totient is φ = 225036000.

The previous prime is 661100623. The next prime is 661100653. The reversal of 661100650 is 56001166.

It is a super-3 number, since 3×661100650³ (a number of 27 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is not an unprimeable number, because it can be changed into a prime (661100653) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 369057 + ... + 370843.

It is an arithmetic number, because the mean of its divisors is an integer number (20009508).

Almost surely, 2^661100650 is an apocalyptic number.

661100650 is an abundant number, since it is smaller than the sum of its proper divisors (779583926).

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

661100650 is a wasteful number, since it uses less digits than its factorization.

661100650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1964 (or 1952 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 25.

The square root of 661100650 is about 25711.8776054959. The cubic root of 661100650 is about 871.1424854653.

The spelling of 661100650 in words is "six hundred sixty-one million, one hundred thousand, six hundred fifty".