661132668 has 96 divisors (see below), whose sum is σ = 1795852800. Its totient is φ = 185414400.

The previous prime is 661132657. The next prime is 661132679. The reversal of 661132668 is 866231166.

661132668 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (661132657) and next prime (661132679).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1263855 + ... + 1264377.

It is an arithmetic number, because the mean of its divisors is an integer number (18706800).

Almost surely, 2^661132668 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 661132668, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (897926400).

661132668 is an abundant number, since it is smaller than the sum of its proper divisors (1134720132).

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

661132668 is a wasteful number, since it uses less digits than its factorization.

661132668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 787 (or 785 counting only the distinct ones).

The product of its digits is 62208, while the sum is 39.

The square root of 661132668 is about 25712.5002284881. The cubic root of 661132668 is about 871.1565487752.

The spelling of 661132668 in words is "six hundred sixty-one million, one hundred thirty-two thousand, six hundred sixty-eight".