15994493 has 2 divisors, whose sum is σ = 15994494. Its totient is φ = 15994492.

The previous prime is 15994483. The next prime is 15994529. The reversal of 15994493 is 39449951.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15784729 + 209764 = 3973^2 + 458^2 .

It is an emirp because it is prime and its reverse (39449951) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 15994493 - 2⁴ = 15994477 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15994403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7997246 + 7997247.

It is an arithmetic number, because the mean of its divisors is an integer number (7997247).

Almost surely, 2^15994493 is an apocalyptic number.

It is an amenable number.

15994493 is a deficient number, since it is larger than the sum of its proper divisors (1).

15994493 is an equidigital number, since it uses as much as digits as its factorization.

15994493 is an evil number, because the sum of its binary digits is even.

The product of its digits is 174960, while the sum is 44.

The square root of 15994493 is about 3999.3115657573. The cubic root of 15994493 is about 251.9552967231.

The spelling of 15994493 in words is "fifteen million, nine hundred ninety-four thousand, four hundred ninety-three".