661883552 has 72 divisors (see below), whose sum is σ = 1441188000. Its totient is φ = 298995840.

The previous prime is 661883549. The next prime is 661883591. The reversal of 661883552 is 255388166.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 770099 + ... + 770957.

It is an arithmetic number, because the mean of its divisors is an integer number (20016500).

Almost surely, 2^661883552 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 661883552, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (720594000).

661883552 is an abundant number, since it is smaller than the sum of its proper divisors (779304448).

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

661883552 is a wasteful number, since it uses less digits than its factorization.

661883552 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1090 (or 1071 counting only the distinct ones).

The product of its digits is 345600, while the sum is 44.

The square root of 661883552 is about 25727.0976209910. The cubic root of 661883552 is about 871.4862304741.

The spelling of 661883552 in words is "six hundred sixty-one million, eight hundred eighty-three thousand, five hundred fifty-two".