2871561 has 32 divisors (see below), whose sum is σ = 4939776. Its totient is φ = 1440000.

The previous prime is 2871509. The next prime is 2871563. The reversal of 2871561 is 1651782.

It is not a de Polignac number, because 2871561 - 2⁷ = 2871433 is a prime.

It is a super-4 number, since 4×2871561⁴ (a number of 27 digits) contains 4444 as substring.

It is not an unprimeable number, because it can be changed into a prime (2871563) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6961 + ... + 7361.

It is an arithmetic number, because the mean of its divisors is an integer number (154368).

2^2871561 is an apocalyptic number.

2871561 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2871561 is a deficient number, since it is larger than the sum of its proper divisors (2068215).

2871561 is a wasteful number, since it uses less digits than its factorization.

2871561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 453.

The product of its digits is 3360, while the sum is 30.

The square root of 2871561 is about 1694.5680865637. The cubic root of 2871561 is about 142.1366303799.

The spelling of 2871561 in words is "two million, eight hundred seventy-one thousand, five hundred sixty-one".