2561867515 has 4 divisors (see below), whose sum is σ = 3074241024. Its totient is φ = 2049494008.

The previous prime is 2561867501. The next prime is 2561867521. The reversal of 2561867515 is 5157681652.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2561867515 - 2²¹ = 2559770363 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 256186747 + ... + 256186756.

It is an arithmetic number, because the mean of its divisors is an integer number (768560256).

Almost surely, 2^2561867515 is an apocalyptic number.

2561867515 is a deficient number, since it is larger than the sum of its proper divisors (512373509).

2561867515 is an equidigital number, since it uses as much as digits as its factorization.

2561867515 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 512373508.

The product of its digits is 504000, while the sum is 46.

The square root of 2561867515 is about 50614.8942012131. The cubic root of 2561867515 is about 1368.3133229160.

The spelling of 2561867515 in words is "two billion, five hundred sixty-one million, eight hundred sixty-seven thousand, five hundred fifteen".