2771981 has 4 divisors (see below), whose sum is σ = 2778432. Its totient is φ = 2765532.

The previous prime is 2771971. The next prime is 2771999. The reversal of 2771981 is 1891772.

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 a de Polignac number, because none of the positive numbers 2^k-2771981 is a prime.

It is a super-2 number, since 2×2771981² = 15367757328722, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2771971) 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, 2531 + ... + 3456.

It is an arithmetic number, because the mean of its divisors is an integer number (694608).

2^2771981 is an apocalyptic number.

It is an amenable number.

2771981 is a deficient number, since it is larger than the sum of its proper divisors (6451).

2771981 is an equidigital number, since it uses as much as digits as its factorization.

2771981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6450.

The product of its digits is 7056, while the sum is 35.

The square root of 2771981 is about 1664.9267251144. The cubic root of 2771981 is about 140.4742589503.

The spelling of 2771981 in words is "two million, seven hundred seventy-one thousand, nine hundred eighty-one".