13898621 has 4 divisors (see below), whose sum is σ = 15162144. Its totient is φ = 12635100.

The previous prime is 13898617. The next prime is 13898629. The reversal of 13898621 is 12689831.

13898621 = 426² + 427² + ... + 491².

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 a cyclic number.

It is not a de Polignac number, because 13898621 - 2² = 13898617 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13898629) 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 3 ways as a sum of consecutive naturals, for example, 631745 + ... + 631766.

It is an arithmetic number, because the mean of its divisors is an integer number (3790536).

Almost surely, 2^13898621 is an apocalyptic number.

13898621 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

13898621 is a deficient number, since it is larger than the sum of its proper divisors (1263523).

13898621 is a wasteful number, since it uses less digits than its factorization.

13898621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1263522.

The product of its digits is 20736, while the sum is 38.

The square root of 13898621 is about 3728.0854335704. The cubic root of 13898621 is about 240.4310598082.

The spelling of 13898621 in words is "thirteen million, eight hundred ninety-eight thousand, six hundred twenty-one".