15997109 has 2 divisors, whose sum is σ = 15997110. Its totient is φ = 15997108.

The previous prime is 15997103. The next prime is 15997123. The reversal of 15997109 is 90179951.

It is a happy number.

15997109 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12096484 + 3900625 = 3478^2 + 1975^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-15997109 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (15997103) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7998554 + 7998555.

It is an arithmetic number, because the mean of its divisors is an integer number (7998555).

Almost surely, 2^15997109 is an apocalyptic number.

It is an amenable number.

15997109 is a deficient number, since it is larger than the sum of its proper divisors (1).

15997109 is an equidigital number, since it uses as much as digits as its factorization.

15997109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25515, while the sum is 41.

The square root of 15997109 is about 3999.6386086745. The cubic root of 15997109 is about 251.9690322658.

The spelling of 15997109 in words is "fifteen million, nine hundred ninety-seven thousand, one hundred nine".