13620640 has 96 divisors (see below), whose sum is σ = 35925120. Its totient is φ = 4838400.

The previous prime is 13620619. The next prime is 13620641. The reversal of 13620640 is 4602631.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a zygodrome in base 3.

It is not an unprimeable number, because it can be changed into a prime (13620641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 124906 + ... + 125014.

It is an arithmetic number, because the mean of its divisors is an integer number (374220).

Almost surely, 2^13620640 is an apocalyptic number.

13620640 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 13620640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17962560).

13620640 is an abundant number, since it is smaller than the sum of its proper divisors (22304480).

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

13620640 is a wasteful number, since it uses less digits than its factorization.

13620640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 206 (or 198 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 22.

The square root of 13620640 is about 3690.6151248809. The cubic root of 13620640 is about 238.8173297675.

Subtracting from 13620640 its reverse (4602631), we obtain a square (9018009 = 3003²).

The spelling of 13620640 in words is "thirteen million, six hundred twenty thousand, six hundred forty".