661801584 has 40 divisors (see below), whose sum is σ = 1738638720. Its totient is φ = 216860608.

The previous prime is 661801577. The next prime is 661801607. The reversal of 661801584 is 485108166.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 114012 + ... + 119675.

It is an arithmetic number, because the mean of its divisors is an integer number (43465968).

Almost surely, 2^661801584 is an apocalyptic number.

It is an amenable number.

661801584 is an abundant number, since it is smaller than the sum of its proper divisors (1076837136).

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

661801584 is a wasteful number, since it uses less digits than its factorization.

661801584 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 233757 (or 233751 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 39.

The square root of 661801584 is about 25725.5045431572. The cubic root of 661801584 is about 871.4502538878.

The spelling of 661801584 in words is "six hundred sixty-one million, eight hundred one thousand, five hundred eighty-four".