13891428 has 36 divisors (see below), whose sum is σ = 36066940. Its totient is φ = 4504896.

The previous prime is 13891399. The next prime is 13891433. The reversal of 13891428 is 82419831.

It can be written as a sum of positive squares in 2 ways, for example, as 13264164 + 627264 = 3642^2 + 792^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 13891392 and 13891401.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3883 + ... + 6546.

Almost surely, 2^13891428 is an apocalyptic number.

13891428 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

13891428 is an abundant number, since it is smaller than the sum of its proper divisors (22175512).

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

13891428 is a wasteful number, since it uses less digits than its factorization.

13891428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10476 (or 10471 counting only the distinct ones).

The product of its digits is 13824, while the sum is 36.

The square root of 13891428 is about 3727.1206044345. The cubic root of 13891428 is about 240.3895756197.

The spelling of 13891428 in words is "thirteen million, eight hundred ninety-one thousand, four hundred twenty-eight".