13900521 has 4 divisors (see below), whose sum is σ = 18534032. Its totient is φ = 9267012.

The previous prime is 13900519. The next prime is 13900553. The reversal of 13900521 is 12500931.

13900521 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 13900521 - 2¹ = 13900519 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13900501) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2316751 + ... + 2316756.

It is an arithmetic number, because the mean of its divisors is an integer number (4633508).

Almost surely, 2^13900521 is an apocalyptic number.

It is an amenable number.

13900521 is a deficient number, since it is larger than the sum of its proper divisors (4633511).

13900521 is an equidigital number, since it uses as much as digits as its factorization.

13900521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4633510.

The product of its (nonzero) digits is 270, while the sum is 21.

The square root of 13900521 is about 3728.3402473487. The cubic root of 13900521 is about 240.4420152884.

The spelling of 13900521 in words is "thirteen million, nine hundred thousand, five hundred twenty-one".