65638980 has 72 divisors (see below), whose sum is σ = 217211904. Its totient is φ = 15912000.

The previous prime is 65638961. The next prime is 65638981. The reversal of 65638980 is 8983656.

65638980 is a `hidden beast` number, since 6 + 5 + 638 + 9 + 8 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (65638981) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 14596 + ... + 18555.

It is an arithmetic number, because the mean of its divisors is an integer number (3016832).

Almost surely, 2^65638980 is an apocalyptic number.

65638980 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

65638980 is an abundant number, since it is smaller than the sum of its proper divisors (151572924).

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

65638980 is a wasteful number, since it uses less digits than its factorization.

65638980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33177 (or 33172 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 45.

The square root of 65638980 is about 8101.7886913940. The cubic root of 65638980 is about 403.3858016725.

The spelling of 65638980 in words is "sixty-five million, six hundred thirty-eight thousand, nine hundred eighty".