663820123 has 2 divisors, whose sum is σ = 663820124. Its totient is φ = 663820122.

The previous prime is 663820067. The next prime is 663820147. The reversal of 663820123 is 321028366.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 663820123 - 2¹⁷ = 663689051 is a prime.

It is not a weakly prime, because it can be changed into another prime (663820823) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 331910061 + 331910062.

It is an arithmetic number, because the mean of its divisors is an integer number (331910062).

Almost surely, 2^663820123 is an apocalyptic number.

663820123 is a deficient number, since it is larger than the sum of its proper divisors (1).

663820123 is an equidigital number, since it uses as much as digits as its factorization.

663820123 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10368, while the sum is 31.

The square root of 663820123 is about 25764.7069263363. The cubic root of 663820123 is about 872.3353484426.

Adding to 663820123 its reverse (321028366), we get a palindrome (984848489).

The spelling of 663820123 in words is "six hundred sixty-three million, eight hundred twenty thousand, one hundred twenty-three".