694640663 has 2 divisors, whose sum is σ = 694640664. Its totient is φ = 694640662.

The previous prime is 694640659. The next prime is 694640669. The reversal of 694640663 is 366046496.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 694640663 - 2² = 694640659 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (694640669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 347320331 + 347320332.

It is an arithmetic number, because the mean of its divisors is an integer number (347320332).

Almost surely, 2^694640663 is an apocalyptic number.

694640663 is a deficient number, since it is larger than the sum of its proper divisors (1).

694640663 is an equidigital number, since it uses as much as digits as its factorization.

694640663 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 559872, while the sum is 44.

The square root of 694640663 is about 26356.0365571153. The cubic root of 694640663 is about 885.6322051297.

The spelling of 694640663 in words is "six hundred ninety-four million, six hundred forty thousand, six hundred sixty-three".