18628997 has 2 divisors, whose sum is σ = 18628998. Its totient is φ = 18628996.

The previous prime is 18628993. The next prime is 18629003. The reversal of 18628997 is 79982681.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17297281 + 1331716 = 4159^2 + 1154^2 .

It is a cyclic number.

It is not a de Polignac number, because 18628997 - 2² = 18628993 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18628993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9314498 + 9314499.

It is an arithmetic number, because the mean of its divisors is an integer number (9314499).

Almost surely, 2^18628997 is an apocalyptic number.

It is an amenable number.

18628997 is a deficient number, since it is larger than the sum of its proper divisors (1).

18628997 is an equidigital number, since it uses as much as digits as its factorization.

18628997 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 435456, while the sum is 50.

The square root of 18628997 is about 4316.1321805524. The cubic root of 18628997 is about 265.0919201710.

The spelling of 18628997 in words is "eighteen million, six hundred twenty-eight thousand, nine hundred ninety-seven".