199978351 has 2 divisors, whose sum is σ = 199978352. Its totient is φ = 199978350.

The previous prime is 199978333. The next prime is 199978369. The reversal of 199978351 is 153879991.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (199978333) and next prime (199978369).

It is an emirp because it is prime and its reverse (153879991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 199978351 - 2⁵ = 199978319 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (199976351) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99989175 + 99989176.

It is an arithmetic number, because the mean of its divisors is an integer number (99989176).

Almost surely, 2^199978351 is an apocalyptic number.

199978351 is a deficient number, since it is larger than the sum of its proper divisors (1).

199978351 is an equidigital number, since it uses as much as digits as its factorization.

199978351 is an evil number, because the sum of its binary digits is even.

The product of its digits is 612360, while the sum is 52.

The square root of 199978351 is about 14141.3701952816. The cubic root of 199978351 is about 584.7824461945.

The spelling of 199978351 in words is "one hundred ninety-nine million, nine hundred seventy-eight thousand, three hundred fifty-one".