199966157 has 4 divisors (see below), whose sum is σ = 201907680. Its totient is φ = 198024636.

The previous prime is 199966147. The next prime is 199966171. The reversal of 199966157 is 751669991.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 751669991 = 1693 ⋅443987.

It is a cyclic number.

It is not a de Polignac number, because 199966157 - 2⁸ = 199965901 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 199966099 and 199966108.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (199966147) 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 in 3 ways as a sum of consecutive naturals, for example, 970607 + ... + 970812.

It is an arithmetic number, because the mean of its divisors is an integer number (50476920).

Almost surely, 2^199966157 is an apocalyptic number.

It is an amenable number.

199966157 is a deficient number, since it is larger than the sum of its proper divisors (1941523).

199966157 is a wasteful number, since it uses less digits than its factorization.

199966157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1941522.

The product of its digits is 918540, while the sum is 53.

The square root of 199966157 is about 14140.9390423691. The cubic root of 199966157 is about 584.7705599377.

The spelling of 199966157 in words is "one hundred ninety-nine million, nine hundred sixty-six thousand, one hundred fifty-seven".