13936981 has 4 divisors (see below), whose sum is σ = 13949964. Its totient is φ = 13924000.

The previous prime is 13936969. The next prime is 13936997. The reversal of 13936981 is 18963931.

13936981 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It can be written as a sum of positive squares in 2 ways, for example, as 10458756 + 3478225 = 3234^2 + 1865^2 .

It is a 3-Lehmer number, since φ(13936981) divides (13936981-1)³.

It is a cyclic number.

It is not a de Polignac number, because 13936981 - 2¹¹ = 13934933 is a prime.

It is a super-2 number, since 2×13936981² = 388478878788722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13936931) 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, 4720 + ... + 7081.

It is an arithmetic number, because the mean of its divisors is an integer number (3487491).

Almost surely, 2^13936981 is an apocalyptic number.

It is an amenable number.

13936981 is a deficient number, since it is larger than the sum of its proper divisors (12983).

13936981 is a wasteful number, since it uses less digits than its factorization.

13936981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12982.

The product of its digits is 34992, while the sum is 40.

The square root of 13936981 is about 3733.2266204987. The cubic root of 13936981 is about 240.6520520775.

The spelling of 13936981 in words is "thirteen million, nine hundred thirty-six thousand, nine hundred eighty-one".