13891993 has 2 divisors, whose sum is σ = 13891994. Its totient is φ = 13891992.

The previous prime is 13891987. The next prime is 13892017. The reversal of 13891993 is 39919831.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13191424 + 700569 = 3632^2 + 837^2 .

It is a cyclic number.

It is not a de Polignac number, because 13891993 - 2⁵ = 13891961 is a prime.

It is not a weakly prime, because it can be changed into another prime (13891903) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6945996 + 6945997.

It is an arithmetic number, because the mean of its divisors is an integer number (6945997).

Almost surely, 2^13891993 is an apocalyptic number.

It is an amenable number.

13891993 is a deficient number, since it is larger than the sum of its proper divisors (1).

13891993 is an equidigital number, since it uses as much as digits as its factorization.

13891993 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 52488, while the sum is 43.

The square root of 13891993 is about 3727.1963994402. The cubic root of 13891993 is about 240.3928346623.

It can be divided in two parts, 13891 and 993, that added together give a square (14884 = 122²).

The spelling of 13891993 in words is "thirteen million, eight hundred ninety-one thousand, nine hundred ninety-three".