13997640 has 64 divisors (see below), whose sum is σ = 42644160. Its totient is φ = 3674880.

The previous prime is 13997629. The next prime is 13997651. The reversal of 13997640 is 4679931.

It is an interprime number because it is at equal distance from previous prime (13997629) and next prime (13997651).

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, 7170 + ... + 8910.

It is an arithmetic number, because the mean of its divisors is an integer number (666315).

Almost surely, 2^13997640 is an apocalyptic number.

13997640 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 13997640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21322080).

13997640 is an abundant number, since it is smaller than the sum of its proper divisors (28646520).

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

13997640 is a wasteful number, since it uses less digits than its factorization.

13997640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1822 (or 1818 counting only the distinct ones).

The product of its (nonzero) digits is 40824, while the sum is 39.

The square root of 13997640 is about 3741.3420052168. The cubic root of 13997640 is about 241.0006829523. Note that the first 3 decimals are identical.

It can be divided in two parts, 139 and 97640, that added together give a palindrome (97779).

The spelling of 13997640 in words is "thirteen million, nine hundred ninety-seven thousand, six hundred forty".