2564981 has 4 divisors (see below), whose sum is σ = 2700000. Its totient is φ = 2429964.

The previous prime is 2564957. The next prime is 2564999. The reversal of 2564981 is 1894652.

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.

It is a cyclic number.

It is not a de Polignac number, because 2564981 - 2⁶ = 2564917 is a prime.

It is a super-2 number, since 2×2564981² = 13158255060722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2564921) 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, 67481 + ... + 67518.

It is an arithmetic number, because the mean of its divisors is an integer number (675000).

2^2564981 is an apocalyptic number.

It is an amenable number.

2564981 is a deficient number, since it is larger than the sum of its proper divisors (135019).

2564981 is a wasteful number, since it uses less digits than its factorization.

2564981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135018.

The product of its digits is 17280, while the sum is 35.

The square root of 2564981 is about 1601.5558060836. Note that the first 3 decimals coincide. The cubic root of 2564981 is about 136.8867410680.

The spelling of 2564981 in words is "two million, five hundred sixty-four thousand, nine hundred eighty-one".