661827584 has 104 divisors (see below), whose sum is σ = 1486568208. Its totient is φ = 291962880.

The previous prime is 661827583. The next prime is 661827601. The reversal of 661827584 is 485728166.

It is not an unprimeable number, because it can be changed into a prime (661827581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1666874 + ... + 1667270.

Almost surely, 2^661827584 is an apocalyptic number.

661827584 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 661827584, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (743284104).

661827584 is an abundant number, since it is smaller than the sum of its proper divisors (824740624).

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

661827584 is a wasteful number, since it uses less digits than its factorization.

661827584 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 469 (or 447 counting only the distinct ones).

The product of its digits is 645120, while the sum is 47.

The square root of 661827584 is about 25726.0098732781. The cubic root of 661827584 is about 871.4616658731.

The spelling of 661827584 in words is "six hundred sixty-one million, eight hundred twenty-seven thousand, five hundred eighty-four".