13634640 has 120 divisors (see below), whose sum is σ = 47441160. Its totient is φ = 3505152.

The previous prime is 13634639. The next prime is 13634681. The reversal of 13634640 is 4643631.

13634640 is a `hidden beast` number, since 13 + 6 + 3 + 4 + 640 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 501264 + 13133376 = 708^2 + 3624^2 .

It is a tau number, because it is divible by the number of its divisors (120).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 20554 + ... + 21206.

It is an arithmetic number, because the mean of its divisors is an integer number (395343).

Almost surely, 2^13634640 is an apocalyptic number.

13634640 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 13634640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23720580).

13634640 is an abundant number, since it is smaller than the sum of its proper divisors (33806520).

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

13634640 is a wasteful number, since it uses less digits than its factorization.

13634640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 701 (or 692 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 27.

The square root of 13634640 is about 3692.5113405378. The cubic root of 13634640 is about 238.8991246941.

The spelling of 13634640 in words is "thirteen million, six hundred thirty-four thousand, six hundred forty".