199434133978 has 4 divisors (see below), whose sum is σ = 299151200970. Its totient is φ = 99717066988.

The previous prime is 199434133963. The next prime is 199434133979. The reversal of 199434133978 is 879331434991.

199434133978 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 194615969409 + 4818164569 = 441153^2 + 69413^2 .

It is not an unprimeable number, because it can be changed into a prime (199434133979) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49858533493 + ... + 49858533496.

Almost surely, 2^199434133978 is an apocalyptic number.

199434133978 is a deficient number, since it is larger than the sum of its proper divisors (99717066992).

199434133978 is an equidigital number, since it uses as much as digits as its factorization.

199434133978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99717066991.

The product of its digits is 17635968, while the sum is 61.

The spelling of 199434133978 in words is "one hundred ninety-nine billion, four hundred thirty-four million, one hundred thirty-three thousand, nine hundred seventy-eight".