199525991 has 12 divisors (see below), whose sum is σ = 245755728. Its totient is φ = 160961472.

The previous prime is 199525981. The next prime is 199525999.

199525991 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 199525991 - 2⁶ = 199525927 is a prime.

It is a Smith number, since the sum of its digits (50) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (199525999) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 118931 + ... + 120596.

It is an arithmetic number, because the mean of its divisors is an integer number (20479644).

Almost surely, 2^199525991 is an apocalyptic number.

199525991 is a deficient number, since it is larger than the sum of its proper divisors (46229737).

199525991 is a wasteful number, since it uses less digits than its factorization.

199525991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 239558 (or 239551 counting only the distinct ones).

The product of its digits is 328050, while the sum is 50.

The square root of 199525991 is about 14125.3669332871. The cubic root of 199525991 is about 584.3411785968.

The spelling of 199525991 in words is "one hundred ninety-nine million, five hundred twenty-five thousand, nine hundred ninety-one".