13991937 has 4 divisors (see below), whose sum is σ = 18655920. Its totient is φ = 9327956.

The previous prime is 13991933. The next prime is 13991953. The reversal of 13991937 is 73919931.

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: 73919931 = 3 ⋅24639977.

It is a cyclic number.

It is not a de Polignac number, because 13991937 - 2² = 13991933 is a prime.

It is not an unprimeable number, because it can be changed into a prime (13991933) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2331987 + ... + 2331992.

It is an arithmetic number, because the mean of its divisors is an integer number (4663980).

It is a Proth number, since it is equal to 427 ⋅ 2¹⁵ + 1 and 427 < 2¹⁵.

Almost surely, 2^13991937 is an apocalyptic number.

It is an amenable number.

13991937 is a deficient number, since it is larger than the sum of its proper divisors (4663983).

13991937 is an equidigital number, since it uses as much as digits as its factorization.

13991937 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4663982.

The product of its digits is 45927, while the sum is 42.

The square root of 13991937 is about 3740.5797678969. The cubic root of 13991937 is about 240.9679485391.

The spelling of 13991937 in words is "thirteen million, nine hundred ninety-one thousand, nine hundred thirty-seven".