18457861 has 2 divisors, whose sum is σ = 18457862. Its totient is φ = 18457860.

The previous prime is 18457841. The next prime is 18457871. The reversal of 18457861 is 16875481.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18105025 + 352836 = 4255^2 + 594^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18457861 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18457811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9228930 + 9228931.

It is an arithmetic number, because the mean of its divisors is an integer number (9228931).

Almost surely, 2^18457861 is an apocalyptic number.

It is an amenable number.

18457861 is a deficient number, since it is larger than the sum of its proper divisors (1).

18457861 is an equidigital number, since it uses as much as digits as its factorization.

18457861 is an evil number, because the sum of its binary digits is even.

The product of its digits is 53760, while the sum is 40.

The square root of 18457861 is about 4296.2612816262. The cubic root of 18457861 is about 264.2776626021.

The spelling of 18457861 in words is "eighteen million, four hundred fifty-seven thousand, eight hundred sixty-one".