2577981 has 8 divisors (see below), whose sum is σ = 3928384. Its totient is φ = 1473120.

The previous prime is 2577947. The next prime is 2577989. The reversal of 2577981 is 1897752.

2577981 = T₂₅₄ + T₂₅₅ + ... + T₃₁₆.

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

It is not a de Polignac number, because 2577981 - 2⁶ = 2577917 is a prime.

It is a super-2 number, since 2×2577981² = 13291972072722, which contains 22 as substring.

It is a Duffinian number.

2577981 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2577989) 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 7 ways as a sum of consecutive naturals, for example, 61360 + ... + 61401.

It is an arithmetic number, because the mean of its divisors is an integer number (491048).

2^2577981 is an apocalyptic number.

2577981 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2577981 is a deficient number, since it is larger than the sum of its proper divisors (1350403).

2577981 is a wasteful number, since it uses less digits than its factorization.

2577981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122771.

The product of its digits is 35280, while the sum is 39.

The square root of 2577981 is about 1605.6092301678. The cubic root of 2577981 is about 137.1176108351.

The spelling of 2577981 in words is "two million, five hundred seventy-seven thousand, nine hundred eighty-one".