18280477 has 2 divisors, whose sum is σ = 18280478. Its totient is φ = 18280476.

The previous prime is 18280463. The next prime is 18280487. The reversal of 18280477 is 77408281.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16695396 + 1585081 = 4086^2 + 1259^2 .

It is an emirp because it is prime and its reverse (77408281) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18280477 - 2¹⁵ = 18247709 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18280417) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9140238 + 9140239.

It is an arithmetic number, because the mean of its divisors is an integer number (9140239).

Almost surely, 2^18280477 is an apocalyptic number.

18280477 is the 2469-th hex number.

It is an amenable number.

18280477 is a deficient number, since it is larger than the sum of its proper divisors (1).

18280477 is an equidigital number, since it uses as much as digits as its factorization.

18280477 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 25088, while the sum is 37.

The square root of 18280477 is about 4275.5674477197. The cubic root of 18280477 is about 263.4283477390.

The spelling of 18280477 in words is "eighteen million, two hundred eighty thousand, four hundred seventy-seven".