15709997 has 2 divisors, whose sum is σ = 15709998. Its totient is φ = 15709996.

The previous prime is 15709961. The next prime is 15710003. The reversal of 15709997 is 79990751.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8031556 + 7678441 = 2834^2 + 2771^2 .

It is an emirp because it is prime and its reverse (79990751) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 15709997 - 2⁶ = 15709933 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 (15709907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7854998 + 7854999.

It is an arithmetic number, because the mean of its divisors is an integer number (7854999).

Almost surely, 2^15709997 is an apocalyptic number.

It is an amenable number.

15709997 is a deficient number, since it is larger than the sum of its proper divisors (1).

15709997 is an equidigital number, since it uses as much as digits as its factorization.

15709997 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 178605, while the sum is 47.

The square root of 15709997 is about 3963.5838580759. The cubic root of 15709997 is about 250.4524978221.

The spelling of 15709997 in words is "fifteen million, seven hundred nine thousand, nine hundred ninety-seven".