661505632 has 48 divisors (see below), whose sum is σ = 1388251872. Its totient is φ = 309196800.

The previous prime is 661505629. The next prime is 661505641. The reversal of 661505632 is 236505166.

661505632 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (34).

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, 78118 + ... + 86170.

It is an arithmetic number, because the mean of its divisors is an integer number (28921914).

Almost surely, 2^661505632 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 661505632, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (694125936).

661505632 is an abundant number, since it is smaller than the sum of its proper divisors (726746240).

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

661505632 is a wasteful number, since it uses less digits than its factorization.

661505632 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8231 (or 8223 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 34.

The square root of 661505632 is about 25719.7517872937. The cubic root of 661505632 is about 871.3203328228.

The spelling of 661505632 in words is "six hundred sixty-one million, five hundred five thousand, six hundred thirty-two".