199961423 has 2 divisors, whose sum is σ = 199961424. Its totient is φ = 199961422.

The previous prime is 199961417. The next prime is 199961441. The reversal of 199961423 is 324169991.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 199961423 - 2⁴ = 199961407 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (199961483) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99980711 + 99980712.

It is an arithmetic number, because the mean of its divisors is an integer number (99980712).

Almost surely, 2^199961423 is an apocalyptic number.

199961423 is a deficient number, since it is larger than the sum of its proper divisors (1).

199961423 is an equidigital number, since it uses as much as digits as its factorization.

199961423 is an evil number, because the sum of its binary digits is even.

The product of its digits is 104976, while the sum is 44.

The square root of 199961423 is about 14140.7716550406. The cubic root of 199961423 is about 584.7659452807.

The spelling of 199961423 in words is "one hundred ninety-nine million, nine hundred sixty-one thousand, four hundred twenty-three".