15990641 has 2 divisors, whose sum is σ = 15990642. Its totient is φ = 15990640.

The previous prime is 15990619. The next prime is 15990643. The reversal of 15990641 is 14609951.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9740641 + 6250000 = 3121^2 + 2500^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-15990641 is a prime.

Together with 15990643, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (15990643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7995320 + 7995321.

It is an arithmetic number, because the mean of its divisors is an integer number (7995321).

Almost surely, 2^15990641 is an apocalyptic number.

It is an amenable number.

15990641 is a deficient number, since it is larger than the sum of its proper divisors (1).

15990641 is an equidigital number, since it uses as much as digits as its factorization.

15990641 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9720, while the sum is 35.

The square root of 15990641 is about 3998.8299538740. The cubic root of 15990641 is about 251.9350687249.

The spelling of 15990641 in words is "fifteen million, nine hundred ninety thousand, six hundred forty-one".