199878031 has 2 divisors, whose sum is σ = 199878032. Its totient is φ = 199878030.

The previous prime is 199878013. The next prime is 199878037. The reversal of 199878031 is 130878991.

Together with previous prime (199878013) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 199878031 - 2¹⁵ = 199845263 is a prime.

It is a super-2 number, since 2×199878031² = 79902454552873922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (199878037) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99939015 + 99939016.

It is an arithmetic number, because the mean of its divisors is an integer number (99939016).

Almost surely, 2^199878031 is an apocalyptic number.

199878031 is a deficient number, since it is larger than the sum of its proper divisors (1).

199878031 is an equidigital number, since it uses as much as digits as its factorization.

199878031 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 108864, while the sum is 46.

The square root of 199878031 is about 14137.8227107288. The cubic root of 199878031 is about 584.6846436285.

The spelling of 199878031 in words is "one hundred ninety-nine million, eight hundred seventy-eight thousand, thirty-one".