13521861 has 12 divisors (see below), whose sum is σ = 20381088. Its totient is φ = 8622504.

The previous prime is 13521829. The next prime is 13521881. The reversal of 13521861 is 16812531.

It is not a de Polignac number, because 13521861 - 2⁵ = 13521829 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13521811) 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 11 ways as a sum of consecutive naturals, for example, 32455 + ... + 32868.

It is an arithmetic number, because the mean of its divisors is an integer number (1698424).

Almost surely, 2^13521861 is an apocalyptic number.

It is an amenable number.

13521861 is a deficient number, since it is larger than the sum of its proper divisors (6859227).

13521861 is a wasteful number, since it uses less digits than its factorization.

13521861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65352 (or 65349 counting only the distinct ones).

The product of its digits is 1440, while the sum is 27.

The square root of 13521861 is about 3677.2083161007. The cubic root of 13521861 is about 238.2386150536.

It can be divided in two parts, 135 and 21861, that multiplied together give a triangular number (2951235 = T₂₄₂₉).

The spelling of 13521861 in words is "thirteen million, five hundred twenty-one thousand, eight hundred sixty-one".