13656491 has 4 divisors (see below), whose sum is σ = 14459832. Its totient is φ = 12853152.

The previous prime is 13656473. The next prime is 13656509. The reversal of 13656491 is 19465631.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19465631 = 1993 ⋅9767.

It is an interprime number because it is at equal distance from previous prime (13656473) and next prime (13656509).

It is a cyclic number.

It is not a de Polignac number, because 13656491 - 2¹⁸ = 13394347 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13656431) 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 3 ways as a sum of consecutive naturals, for example, 401645 + ... + 401678.

It is an arithmetic number, because the mean of its divisors is an integer number (3614958).

Almost surely, 2^13656491 is an apocalyptic number.

13656491 is a deficient number, since it is larger than the sum of its proper divisors (803341).

13656491 is an equidigital number, since it uses as much as digits as its factorization.

13656491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 803340.

The product of its digits is 19440, while the sum is 35.

The square root of 13656491 is about 3695.4689824162. The cubic root of 13656491 is about 239.0266772274.

The spelling of 13656491 in words is "thirteen million, six hundred fifty-six thousand, four hundred ninety-one".