15698561 has 2 divisors, whose sum is σ = 15698562. Its totient is φ = 15698560.

The previous prime is 15698549. The next prime is 15698563. The reversal of 15698561 is 16589651.

15698561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8300161 + 7398400 = 2881^2 + 2720^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-15698561 is a prime.

Together with 15698563, 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 (15698563) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7849280 + 7849281.

It is an arithmetic number, because the mean of its divisors is an integer number (7849281).

Almost surely, 2^15698561 is an apocalyptic number.

It is an amenable number.

15698561 is a deficient number, since it is larger than the sum of its proper divisors (1).

15698561 is an equidigital number, since it uses as much as digits as its factorization.

15698561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 64800, while the sum is 41.

The square root of 15698561 is about 3962.1409616519. The cubic root of 15698561 is about 250.3917112619.

The spelling of 15698561 in words is "fifteen million, six hundred ninety-eight thousand, five hundred sixty-one".