2881561 has 2 divisors, whose sum is σ = 2881562. Its totient is φ = 2881560.

The previous prime is 2881547. The next prime is 2881573. The reversal of 2881561 is 1651882.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1547536 + 1334025 = 1244^2 + 1155^2 .

It is a cyclic number.

It is not a de Polignac number, because 2881561 - 2⁷ = 2881433 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (2881531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1440780 + 1440781.

It is an arithmetic number, because the mean of its divisors is an integer number (1440781).

2^2881561 is an apocalyptic number.

It is an amenable number.

2881561 is a deficient number, since it is larger than the sum of its proper divisors (1).

2881561 is an equidigital number, since it uses as much as digits as its factorization.

2881561 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3840, while the sum is 31.

The square root of 2881561 is about 1697.5161265802. The cubic root of 2881561 is about 142.3014326778.

It can be divided in two parts, 288 and 1561, that added together give a square (1849 = 43²).

The spelling of 2881561 in words is "two million, eight hundred eighty-one thousand, five hundred sixty-one".