13981357 has 4 divisors (see below), whose sum is σ = 15056860. Its totient is φ = 12905856.

The previous prime is 13981351. The next prime is 13981379. The reversal of 13981357 is 75318931.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 75318931 = 83 ⋅907457.

It can be written as a sum of positive squares in 2 ways, for example, as 978121 + 13003236 = 989^2 + 3606^2 .

It is a cyclic number.

It is not a de Polignac number, because 13981357 - 2³ = 13981349 is a prime.

It is a super-2 number, since 2×13981357² = 390956687122898, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13981351) 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, 537732 + ... + 537757.

It is an arithmetic number, because the mean of its divisors is an integer number (3764215).

Almost surely, 2^13981357 is an apocalyptic number.

It is an amenable number.

13981357 is a deficient number, since it is larger than the sum of its proper divisors (1075503).

13981357 is a wasteful number, since it uses less digits than its factorization.

13981357 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1075502.

The product of its digits is 22680, while the sum is 37.

The square root of 13981357 is about 3739.1652811824. The cubic root of 13981357 is about 240.9071972709.

The spelling of 13981357 in words is "thirteen million, nine hundred eighty-one thousand, three hundred fifty-seven".