15128561 has 8 divisors (see below), whose sum is σ = 17692224. Its totient is φ = 12665520.

The previous prime is 15128551. The next prime is 15128563. The reversal of 15128561 is 16582151.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 15128561 - 2⁶ = 15128497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15128563) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24830 + ... + 25431.

It is an arithmetic number, because the mean of its divisors is an integer number (2211528).

Almost surely, 2^15128561 is an apocalyptic number.

It is an amenable number.

15128561 is a deficient number, since it is larger than the sum of its proper divisors (2563663).

15128561 is an equidigital number, since it uses as much as digits as its factorization.

15128561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50311.

The product of its digits is 2400, while the sum is 29.

The square root of 15128561 is about 3889.5450890818. The cubic root of 15128561 is about 247.3237789231.

The spelling of 15128561 in words is "fifteen million, one hundred twenty-eight thousand, five hundred sixty-one".