13931997 has 16 divisors (see below), whose sum is σ = 20405760. Its totient is φ = 8415792.

The previous prime is 13931987. The next prime is 13931999. The reversal of 13931997 is 79913931.

It is not a de Polignac number, because 13931997 - 2⁶ = 13931933 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13931999) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4003 + ... + 6624.

It is an arithmetic number, because the mean of its divisors is an integer number (1275360).

Almost surely, 2^13931997 is an apocalyptic number.

It is an amenable number.

13931997 is a deficient number, since it is larger than the sum of its proper divisors (6473763).

13931997 is a wasteful number, since it uses less digits than its factorization.

13931997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10672.

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

The square root of 13931997 is about 3732.5590417299. The cubic root of 13931997 is about 240.6233621522.

The spelling of 13931997 in words is "thirteen million, nine hundred thirty-one thousand, nine hundred ninety-seven".