18518477 has 2 divisors, whose sum is σ = 18518478. Its totient is φ = 18518476.

The previous prime is 18518471. The next prime is 18518503. The reversal of 18518477 is 77481581.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15792676 + 2725801 = 3974^2 + 1651^2 .

It is a cyclic number.

It is not a de Polignac number, because 18518477 - 2⁶ = 18518413 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18518471) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9259238 + 9259239.

It is an arithmetic number, because the mean of its divisors is an integer number (9259239).

Almost surely, 2^18518477 is an apocalyptic number.

It is an amenable number.

18518477 is a deficient number, since it is larger than the sum of its proper divisors (1).

18518477 is an equidigital number, since it uses as much as digits as its factorization.

18518477 is an evil number, because the sum of its binary digits is even.

The product of its digits is 62720, while the sum is 41.

The square root of 18518477 is about 4303.3100051007. The cubic root of 18518477 is about 264.5666442749.

The spelling of 18518477 in words is "eighteen million, five hundred eighteen thousand, four hundred seventy-seven".