199961407 has 2 divisors, whose sum is σ = 199961408. Its totient is φ = 199961406.

The previous prime is 199961401. The next prime is 199961417. The reversal of 199961407 is 704169991.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-199961407 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (199961401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99980703 + 99980704.

It is an arithmetic number, because the mean of its divisors is an integer number (99980704).

Almost surely, 2^199961407 is an apocalyptic number.

199961407 is a deficient number, since it is larger than the sum of its proper divisors (1).

199961407 is an equidigital number, since it uses as much as digits as its factorization.

199961407 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 122472, while the sum is 46.

The square root of 199961407 is about 14140.7710893006. The cubic root of 199961407 is about 584.7659296840.

The spelling of 199961407 in words is "one hundred ninety-nine million, nine hundred sixty-one thousand, four hundred seven".