18810457 has 4 divisors (see below), whose sum is σ = 18983140. Its totient is φ = 18637776.

The previous prime is 18810443. The next prime is 18810461. The reversal of 18810457 is 75401881.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 75401881 = 53 ⋅1422677.

It can be written as a sum of positive squares in 2 ways, for example, as 9144576 + 9665881 = 3024^2 + 3109^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18810457 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18810427) 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, 86178 + ... + 86395.

It is an arithmetic number, because the mean of its divisors is an integer number (4745785).

Almost surely, 2^18810457 is an apocalyptic number.

It is an amenable number.

18810457 is a deficient number, since it is larger than the sum of its proper divisors (172683).

18810457 is a wasteful number, since it uses less digits than its factorization.

18810457 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 172682.

The product of its (nonzero) digits is 8960, while the sum is 34.

The square root of 18810457 is about 4337.1023737053. The cubic root of 18810457 is about 265.9498699509.

The spelling of 18810457 in words is "eighteen million, eight hundred ten thousand, four hundred fifty-seven".