18866457 has 6 divisors (see below), whose sum is σ = 27251562. Its totient is φ = 12577632.

The previous prime is 18866453. The next prime is 18866461. The reversal of 18866457 is 75466881.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (18866453) and next prime (18866461).

It can be written as a sum of positive squares in only one way, i.e., 13571856 + 5294601 = 3684^2 + 2301^2 .

It is not a de Polignac number, because 18866457 - 2² = 18866453 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18866453) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1048128 + ... + 1048145.

It is an arithmetic number, because the mean of its divisors is an integer number (4541927).

Almost surely, 2^18866457 is an apocalyptic number.

It is an amenable number.

18866457 is a deficient number, since it is larger than the sum of its proper divisors (8385105).

18866457 is a wasteful number, since it uses less digits than its factorization.

18866457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2096279 (or 2096276 counting only the distinct ones).

The product of its digits is 322560, while the sum is 45.

The square root of 18866457 is about 4343.5534991525. The cubic root of 18866457 is about 266.2135253876.

The spelling of 18866457 in words is "eighteen million, eight hundred sixty-six thousand, four hundred fifty-seven".