2561977 has 4 divisors (see below), whose sum is σ = 2794896. Its totient is φ = 2329060.

The previous prime is 2561969. The next prime is 2561981. The reversal of 2561977 is 7791652.

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 2561977 - 2³ = 2561969 is a prime.

It is a super-2 number, since 2×2561977² = 13127452297058, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2561927) 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, 116443 + ... + 116464.

It is an arithmetic number, because the mean of its divisors is an integer number (698724).

2^2561977 is an apocalyptic number.

It is an amenable number.

2561977 is a deficient number, since it is larger than the sum of its proper divisors (232919).

2561977 is a wasteful number, since it uses less digits than its factorization.

2561977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 232918.

The product of its digits is 26460, while the sum is 37.

The square root of 2561977 is about 1600.6176932672. The cubic root of 2561977 is about 136.8332814901.

The spelling of 2561977 in words is "two million, five hundred sixty-one thousand, nine hundred seventy-seven".