2551665 has 8 divisors (see below), whose sum is σ = 4082688. Its totient is φ = 1360880.

The previous prime is 2551657. The next prime is 2551687. The reversal of 2551665 is 5661552.

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

It is not a de Polignac number, because 2551665 - 2³ = 2551657 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 85041 + ... + 85070.

It is an arithmetic number, because the mean of its divisors is an integer number (510336).

2^2551665 is an apocalyptic number.

It is an amenable number.

2551665 is a deficient number, since it is larger than the sum of its proper divisors (1531023).

2551665 is a wasteful number, since it uses less digits than its factorization.

2551665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 170119.

The product of its digits is 9000, while the sum is 30.

The square root of 2551665 is about 1597.3931889175. The cubic root of 2551665 is about 136.6494492158.

The spelling of 2551665 in words is "two million, five hundred fifty-one thousand, six hundred sixty-five".