18283621 has 2 divisors, whose sum is σ = 18283622. Its totient is φ = 18283620.

The previous prime is 18283613. The next prime is 18283651. The reversal of 18283621 is 12638281.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16564900 + 1718721 = 4070^2 + 1311^2 .

It is a cyclic number.

It is not a de Polignac number, because 18283621 - 2³ = 18283613 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18283651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9141810 + 9141811.

It is an arithmetic number, because the mean of its divisors is an integer number (9141811).

Almost surely, 2^18283621 is an apocalyptic number.

It is an amenable number.

18283621 is a deficient number, since it is larger than the sum of its proper divisors (1).

18283621 is an equidigital number, since it uses as much as digits as its factorization.

18283621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4608, while the sum is 31.

The square root of 18283621 is about 4275.9351024074. The cubic root of 18283621 is about 263.4434489359.

The spelling of 18283621 in words is "eighteen million, two hundred eighty-three thousand, six hundred twenty-one".