13902561 has 6 divisors (see below), whose sum is σ = 20081490. Its totient is φ = 9268368.

The previous prime is 13902541. The next prime is 13902587. The reversal of 13902561 is 16520931.

13902561 is a `hidden beast` number, since 13 + 90 + 2 + 561 = 666.

It can be written as a sum of positive squares in only one way, i.e., 9492561 + 4410000 = 3081^2 + 2100^2 .

It is not a de Polignac number, because 13902561 - 2⁵ = 13902529 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (13902541) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 772356 + ... + 772373.

It is an arithmetic number, because the mean of its divisors is an integer number (3346915).

Almost surely, 2^13902561 is an apocalyptic number.

It is an amenable number.

13902561 is a deficient number, since it is larger than the sum of its proper divisors (6178929).

13902561 is a wasteful number, since it uses less digits than its factorization.

13902561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1544735 (or 1544732 counting only the distinct ones).

The product of its (nonzero) digits is 1620, while the sum is 27.

The square root of 13902561 is about 3728.6138174930. The cubic root of 13902561 is about 240.4537769031.

The spelling of 13902561 in words is "thirteen million, nine hundred two thousand, five hundred sixty-one".