199439551 has 4 divisors (see below), whose sum is σ = 199472400. Its totient is φ = 199406704.

The previous prime is 199439543. The next prime is 199439557. The reversal of 199439551 is 155934991.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 199439551 - 2³ = 199439543 is a prime.

It is a super-2 number, since 2×199439551² = 79552269006163202, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (199439557) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4366 + ... + 20443.

It is an arithmetic number, because the mean of its divisors is an integer number (49868100).

Almost surely, 2^199439551 is an apocalyptic number.

199439551 is a deficient number, since it is larger than the sum of its proper divisors (32849).

199439551 is an equidigital number, since it uses as much as digits as its factorization.

199439551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32848.

The product of its digits is 218700, while the sum is 46.

The square root of 199439551 is about 14122.3068583005. The cubic root of 199439551 is about 584.2567823282.

The spelling of 199439551 in words is "one hundred ninety-nine million, four hundred thirty-nine thousand, five hundred fifty-one".