2566381 has 4 divisors (see below), whose sum is σ = 2569600. Its totient is φ = 2563164.

The previous prime is 2566367. The next prime is 2566411. The reversal of 2566381 is 1836652.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 2566381 - 2⁷ = 2566253 is a prime.

It is a super-2 number, since 2×2566381² = 13172622874322, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2566351) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 580 + ... + 2338.

It is an arithmetic number, because the mean of its divisors is an integer number (642400).

2^2566381 is an apocalyptic number.

It is an amenable number.

2566381 is a deficient number, since it is larger than the sum of its proper divisors (3219).

2566381 is a wasteful number, since it uses less digits than its factorization.

2566381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3218.

The product of its digits is 8640, while the sum is 31.

The square root of 2566381 is about 1601.9928214571. The cubic root of 2566381 is about 136.9116413929.

The spelling of 2566381 in words is "two million, five hundred sixty-six thousand, three hundred eighty-one".