199991054 has 4 divisors (see below), whose sum is σ = 299986584. Its totient is φ = 99995526.

The previous prime is 199991053. The next prime is 199991059. The reversal of 199991054 is 450199991.

It is a happy number.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (199991053) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49997762 + ... + 49997765.

It is an arithmetic number, because the mean of its divisors is an integer number (74996646).

Almost surely, 2^199991054 is an apocalyptic number.

199991054 is a deficient number, since it is larger than the sum of its proper divisors (99995530).

199991054 is an equidigital number, since it uses as much as digits as its factorization.

199991054 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99995529.

The product of its (nonzero) digits is 131220, while the sum is 47.

The square root of 199991054 is about 14141.8193313307. The cubic root of 199991054 is about 584.7948280917.

The spelling of 199991054 in words is "one hundred ninety-nine million, nine hundred ninety-one thousand, fifty-four".