13978931 has 2 divisors, whose sum is σ = 13978932. Its totient is φ = 13978930.

The previous prime is 13978901. The next prime is 13978949. The reversal of 13978931 is 13987931.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 13978931 - 2¹⁴ = 13962547 is a prime.

It is a super-2 number, since 2×13978931² = 390821023805522, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (13978901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6989465 + 6989466.

It is an arithmetic number, because the mean of its divisors is an integer number (6989466).

Almost surely, 2^13978931 is an apocalyptic number.

13978931 is a deficient number, since it is larger than the sum of its proper divisors (1).

13978931 is an equidigital number, since it uses as much as digits as its factorization.

13978931 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 40824, while the sum is 41.

The square root of 13978931 is about 3738.8408631553. The cubic root of 13978931 is about 240.8932626515.

The spelling of 13978931 in words is "thirteen million, nine hundred seventy-eight thousand, nine hundred thirty-one".