13913681 has 4 divisors (see below), whose sum is σ = 14646000. Its totient is φ = 13181364.

The previous prime is 13913677. The next prime is 13913687. The reversal of 13913681 is 18631931.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18631931 = 179 ⋅104089.

It is not a de Polignac number, because 13913681 - 2² = 13913677 is a prime.

It is a super-2 number, since 2×13913681² = 387181037939522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13913687) 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, 366131 + ... + 366168.

It is an arithmetic number, because the mean of its divisors is an integer number (3661500).

Almost surely, 2^13913681 is an apocalyptic number.

It is an amenable number.

13913681 is a deficient number, since it is larger than the sum of its proper divisors (732319).

13913681 is an equidigital number, since it uses as much as digits as its factorization.

13913681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 732318.

The product of its digits is 3888, while the sum is 32.

The square root of 13913681 is about 3730.1046902198. The cubic root of 13913681 is about 240.5178690135.

The spelling of 13913681 in words is "thirteen million, nine hundred thirteen thousand, six hundred eighty-one".