18376621 has 2 divisors, whose sum is σ = 18376622. Its totient is φ = 18376620.

The previous prime is 18376607. The next prime is 18376639. The reversal of 18376621 is 12667381.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12320100 + 6056521 = 3510^2 + 2461^2 .

It is an emirp because it is prime and its reverse (12667381) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 18376621 - 2¹³ = 18368429 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18376601) 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 as a sum of consecutive naturals, namely, 9188310 + 9188311.

It is an arithmetic number, because the mean of its divisors is an integer number (9188311).

Almost surely, 2^18376621 is an apocalyptic number.

It is an amenable number.

18376621 is a deficient number, since it is larger than the sum of its proper divisors (1).

18376621 is an equidigital number, since it uses as much as digits as its factorization.

18376621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 12096, while the sum is 34.

The square root of 18376621 is about 4286.7961229804. The cubic root of 18376621 is about 263.8893638420.

The spelling of 18376621 in words is "eighteen million, three hundred seventy-six thousand, six hundred twenty-one".