13993537 has 4 divisors (see below), whose sum is σ = 14257620. Its totient is φ = 13729456.

The previous prime is 13993523. The next prime is 13993541. The reversal of 13993537 is 73539931.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 73539931 = 3863 ⋅19037.

It can be written as a sum of positive squares in 2 ways, for example, as 4562496 + 9431041 = 2136^2 + 3071^2 .

It is a cyclic number.

It is not a de Polignac number, because 13993537 - 2⁷ = 13993409 is a prime.

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 13993537.

It is not an unprimeable number, because it can be changed into a prime (13993517) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 131962 + ... + 132067.

It is an arithmetic number, because the mean of its divisors is an integer number (3564405).

Almost surely, 2^13993537 is an apocalyptic number.

It is an amenable number.

13993537 is a deficient number, since it is larger than the sum of its proper divisors (264083).

13993537 is an equidigital number, since it uses as much as digits as its factorization.

13993537 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 264082.

The product of its digits is 76545, while the sum is 40.

The square root of 13993537 is about 3740.7936323727. The cubic root of 13993537 is about 240.9771332103.

The spelling of 13993537 in words is "thirteen million, nine hundred ninety-three thousand, five hundred thirty-seven".