13861638 has 32 divisors (see below), whose sum is σ = 35205120. Its totient is φ = 3960360.

The previous prime is 13861633. The next prime is 13861651. The reversal of 13861638 is 83616831.

13861638 is a `hidden beast` number, since 1 + 3 + 8 + 616 + 38 = 666.

It is a super-3 number, since 3×13861638³ (a number of 22 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13861633) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17958 + ... + 18713.

It is an arithmetic number, because the mean of its divisors is an integer number (1100160).

Almost surely, 2^13861638 is an apocalyptic number.

13861638 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

13861638 is an abundant number, since it is smaller than the sum of its proper divisors (21343482).

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

13861638 is a wasteful number, since it uses less digits than its factorization.

13861638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36689 (or 36683 counting only the distinct ones).

The product of its digits is 20736, while the sum is 36.

The square root of 13861638 is about 3723.1220769671. The cubic root of 13861638 is about 240.2176151223.

It can be divided in two parts, 138 and 61638, that added together give a triangular number (61776 = T₃₅₁).

The spelling of 13861638 in words is "thirteen million, eight hundred sixty-one thousand, six hundred thirty-eight".