13640427 has 8 divisors (see below), whose sum is σ = 20208080. Its totient is φ = 9093600.

The previous prime is 13640401. The next prime is 13640437. The reversal of 13640427 is 72404631.

13640427 is a `hidden beast` number, since 13 + 640 + 4 + 2 + 7 = 666.

It is not a de Polignac number, because 13640427 - 2⁷ = 13640299 is a prime.

It is a super-2 number, since 2×13640427² = 372122497484658, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 505201 = 13640427 / (1 + 3 + 6 + 4 + 0 + 4 + 2 + 7).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 13640427.

It is not an unprimeable number, because it can be changed into a prime (13640437) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 252574 + ... + 252627.

It is an arithmetic number, because the mean of its divisors is an integer number (2526010).

Almost surely, 2^13640427 is an apocalyptic number.

13640427 is a deficient number, since it is larger than the sum of its proper divisors (6567653).

13640427 is an equidigital number, since it uses as much as digits as its factorization.

13640427 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 505210 (or 505204 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 27.

The square root of 13640427 is about 3693.2948704375. The cubic root of 13640427 is about 238.9329188558.

The spelling of 13640427 in words is "thirteen million, six hundred forty thousand, four hundred twenty-seven".