13921431 has 4 divisors (see below), whose sum is σ = 18561912. Its totient is φ = 9280952.

The previous prime is 13921429. The next prime is 13921451. The reversal of 13921431 is 13412931.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 13921431 - 2¹ = 13921429 is a prime.

It is a super-2 number, since 2×13921431² = 387612482175522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13921451) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2320236 + ... + 2320241.

It is an arithmetic number, because the mean of its divisors is an integer number (4640478).

Almost surely, 2^13921431 is an apocalyptic number.

13921431 is a deficient number, since it is larger than the sum of its proper divisors (4640481).

13921431 is an equidigital number, since it uses as much as digits as its factorization.

13921431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4640480.

The product of its digits is 648, while the sum is 24.

The square root of 13921431 is about 3731.1433904368. The cubic root of 13921431 is about 240.5625173349.

The spelling of 13921431 in words is "thirteen million, nine hundred twenty-one thousand, four hundred thirty-one".