15989971 has 2 divisors, whose sum is σ = 15989972. Its totient is φ = 15989970.

The previous prime is 15989951. The next prime is 15989983. The reversal of 15989971 is 17998951.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-15989971 is a prime.

It is not a weakly prime, because it can be changed into another prime (15989921) 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, 7994985 + 7994986.

It is an arithmetic number, because the mean of its divisors is an integer number (7994986).

Almost surely, 2^15989971 is an apocalyptic number.

15989971 is a deficient number, since it is larger than the sum of its proper divisors (1).

15989971 is an equidigital number, since it uses as much as digits as its factorization.

15989971 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 204120, while the sum is 49.

The square root of 15989971 is about 3998.7461784915. The cubic root of 15989971 is about 251.9315500239.

The spelling of 15989971 in words is "fifteen million, nine hundred eighty-nine thousand, nine hundred seventy-one".