18912461 has 2 divisors, whose sum is σ = 18912462. Its totient is φ = 18912460.

The previous prime is 18912451. The next prime is 18912469. The reversal of 18912461 is 16421981.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13764100 + 5148361 = 3710^2 + 2269^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18912461 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18912469) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9456230 + 9456231.

It is an arithmetic number, because the mean of its divisors is an integer number (9456231).

Almost surely, 2^18912461 is an apocalyptic number.

It is an amenable number.

18912461 is a deficient number, since it is larger than the sum of its proper divisors (1).

18912461 is an equidigital number, since it uses as much as digits as its factorization.

18912461 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3456, while the sum is 32.

The square root of 18912461 is about 4348.8459388670. The cubic root of 18912461 is about 266.4297282533.

The spelling of 18912461 in words is "eighteen million, nine hundred twelve thousand, four hundred sixty-one".