2561815 has 8 divisors (see below), whose sum is σ = 3255120. Its totient is φ = 1928832.

The previous prime is 2561813. The next prime is 2561821. The reversal of 2561815 is 5181652.

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

It is a cyclic number.

It is not a de Polignac number, because 2561815 - 2¹ = 2561813 is a prime.

2561815 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2561813) 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, 14985 + ... + 15154.

It is an arithmetic number, because the mean of its divisors is an integer number (406890).

2^2561815 is an apocalyptic number.

2561815 is a deficient number, since it is larger than the sum of its proper divisors (693305).

2561815 is a wasteful number, since it uses less digits than its factorization.

2561815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30161.

The product of its digits is 2400, while the sum is 28.

The square root of 2561815 is about 1600.5670870039. The cubic root of 2561815 is about 136.8303973296.

The spelling of 2561815 in words is "two million, five hundred sixty-one thousand, eight hundred fifteen".