2645861 has 2 divisors, whose sum is σ = 2645862. Its totient is φ = 2645860.

The previous prime is 2645849. The next prime is 2645879. The reversal of 2645861 is 1685462.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2608225 + 37636 = 1615^2 + 194^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2645861 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2645831) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1322930 + 1322931.

It is an arithmetic number, because the mean of its divisors is an integer number (1322931).

2^2645861 is an apocalyptic number.

It is an amenable number.

2645861 is a deficient number, since it is larger than the sum of its proper divisors (1).

2645861 is an equidigital number, since it uses as much as digits as its factorization.

2645861 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11520, while the sum is 32.

The square root of 2645861 is about 1626.6102790773. The cubic root of 2645861 is about 138.3106667592.

The spelling of 2645861 in words is "two million, six hundred forty-five thousand, eight hundred sixty-one".