199964623 has 2 divisors, whose sum is σ = 199964624. Its totient is φ = 199964622.

The previous prime is 199964621. The next prime is 199964669. The reversal of 199964623 is 326469991.

It is a weak prime.

It is an emirp because it is prime and its reverse (326469991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 199964623 - 2¹ = 199964621 is a prime.

Together with 199964621, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (199964621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99982311 + 99982312.

It is an arithmetic number, because the mean of its divisors is an integer number (99982312).

Almost surely, 2^199964623 is an apocalyptic number.

199964623 is a deficient number, since it is larger than the sum of its proper divisors (1).

199964623 is an equidigital number, since it uses as much as digits as its factorization.

199964623 is an evil number, because the sum of its binary digits is even.

The product of its digits is 629856, while the sum is 49.

The square root of 199964623 is about 14140.8848025857. The cubic root of 199964623 is about 584.7690646175.

The spelling of 199964623 in words is "one hundred ninety-nine million, nine hundred sixty-four thousand, six hundred twenty-three".