2561767 has 4 divisors (see below), whose sum is σ = 2758840. Its totient is φ = 2364696.

The previous prime is 2561761. The next prime is 2561771. The reversal of 2561767 is 7671652.

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 2561767 - 2³ = 2561759 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2561761) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 98517 + ... + 98542.

It is an arithmetic number, because the mean of its divisors is an integer number (689710).

2^2561767 is an apocalyptic number.

2561767 is a deficient number, since it is larger than the sum of its proper divisors (197073).

2561767 is a wasteful number, since it uses less digits than its factorization.

2561767 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 197072.

The product of its digits is 17640, while the sum is 34.

The square root of 2561767 is about 1600.5520922482. The cubic root of 2561767 is about 136.8295427401.

The spelling of 2561767 in words is "two million, five hundred sixty-one thousand, seven hundred sixty-seven".