13656780 has 72 divisors (see below), whose sum is σ = 43872192. Its totient is φ = 3426816.

The previous prime is 13656761. The next prime is 13656781. The reversal of 13656780 is 8765631.

13656780 is a `hidden beast` number, since 13 + 6 + 567 + 80 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (13656781) 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, 829 + ... + 5291.

It is an arithmetic number, because the mean of its divisors is an integer number (609336).

Almost surely, 2^13656780 is an apocalyptic number.

13656780 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 13656780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21936096).

13656780 is an abundant number, since it is smaller than the sum of its proper divisors (30215412).

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

13656780 is a wasteful number, since it uses less digits than its factorization.

13656780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4495 (or 4490 counting only the distinct ones).

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

The square root of 13656780 is about 3695.5080841476. The cubic root of 13656780 is about 239.0283633174.

The spelling of 13656780 in words is "thirteen million, six hundred fifty-six thousand, seven hundred eighty".