684563623 has 2 divisors, whose sum is σ = 684563624. Its totient is φ = 684563622.

The previous prime is 684563617. The next prime is 684563639. The reversal of 684563623 is 326365486.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 684563623 - 2²¹ = 682466471 is a prime.

It is a super-2 number, since 2×684563623² = 937254707869772258, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 684563623.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (684563923) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 342281811 + 342281812.

It is an arithmetic number, because the mean of its divisors is an integer number (342281812).

Almost surely, 2^684563623 is an apocalyptic number.

684563623 is a deficient number, since it is larger than the sum of its proper divisors (1).

684563623 is an equidigital number, since it uses as much as digits as its factorization.

684563623 is an evil number, because the sum of its binary digits is even.

The product of its digits is 622080, while the sum is 43.

The square root of 684563623 is about 26164.1667744264. The cubic root of 684563623 is about 881.3287532323.

The spelling of 684563623 in words is "six hundred eighty-four million, five hundred sixty-three thousand, six hundred twenty-three".