133665680 has 40 divisors (see below), whose sum is σ = 316051200. Its totient is φ = 52558208.

The previous prime is 133665677. The next prime is 133665733. The reversal of 133665680 is 86566331.

It is a tau number, because it is divible by the number of its divisors (40).

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, 9440 + ... + 18879.

It is an arithmetic number, because the mean of its divisors is an integer number (7901280).

Almost surely, 2^133665680 is an apocalyptic number.

133665680 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

133665680 is the 9440-th pentagonal number.

It is an amenable number.

133665680 is an abundant number, since it is smaller than the sum of its proper divisors (182385520).

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

133665680 is a wasteful number, since it uses less digits than its factorization.

133665680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28391 (or 28385 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 38.

The square root of 133665680 is about 11561.3874599894. The cubic root of 133665680 is about 511.2970700500.

The spelling of 133665680 in words is "one hundred thirty-three million, six hundred sixty-five thousand, six hundred eighty".