13665780 has 48 divisors (see below), whose sum is σ = 42517440. Its totient is φ = 3644064.

The previous prime is 13665763. The next prime is 13665791. The reversal of 13665780 is 8756631.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12114 + ... + 13193.

It is an arithmetic number, because the mean of its divisors is an integer number (885780).

Almost surely, 2^13665780 is an apocalyptic number.

13665780 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

13665780 is an abundant number, since it is smaller than the sum of its proper divisors (28851660).

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

13665780 is a wasteful number, since it uses less digits than its factorization.

13665780 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25325 (or 25317 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

The square root of 13665780 is about 3696.7255781299. The cubic root of 13665780 is about 239.0808594128.

The spelling of 13665780 in words is "thirteen million, six hundred sixty-five thousand, seven hundred eighty".