189999997 has 8 divisors (see below), whose sum is σ = 208040832. Its totient is φ = 172087200.

The previous prime is 189999989. The next prime is 190000003. The reversal of 189999997 is 799999981.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 189999997 - 2³ = 189999989 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (189999907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28888 + ... + 34849.

It is an arithmetic number, because the mean of its divisors is an integer number (26005104).

Almost surely, 2^189999997 is an apocalyptic number.

It is an amenable number.

189999997 is a deficient number, since it is larger than the sum of its proper divisors (18040835).

189999997 is a wasteful number, since it uses less digits than its factorization.

189999997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64019.

The product of its digits is 29760696, while the sum is 70.

The square root of 189999997 is about 13784.0486432688. The cubic root of 189999997 is about 574.8897048687.

It can be divided in two parts, 1 and 89999997, that added together give a palindrome (89999998).

The spelling of 189999997 in words is "one hundred eighty-nine million, nine hundred ninety-nine thousand, nine hundred ninety-seven".