660376638 has 40 divisors (see below), whose sum is σ = 1488349368. Its totient is φ = 218843856.

The previous prime is 660376637. The next prime is 660376657. The reversal of 660376638 is 836673066.

660376638 is a `hidden beast` number, since 6 + 6 + 0 + 3 + 7 + 6 + 638 = 666.

It is a junction number, because it is equal to n+sod(n) for n = 660376593 and 660376602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (660376637) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 16245 + ... + 39807.

Almost surely, 2^660376638 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 660376638, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (744174684).

660376638 is an abundant number, since it is smaller than the sum of its proper divisors (827972730).

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

660376638 is a wasteful number, since it uses less digits than its factorization.

660376638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23750 (or 23741 counting only the distinct ones).

The product of its (nonzero) digits is 653184, while the sum is 45.

The square root of 660376638 is about 25697.7944189769. The cubic root of 660376638 is about 870.8243553897.

The spelling of 660376638 in words is "six hundred sixty million, three hundred seventy-six thousand, six hundred thirty-eight".