189906821717 has 8 divisors (see below), whose sum is σ = 196366824192. Its totient is φ = 183467692800.

The previous prime is 189906821693. The next prime is 189906821719. The reversal of 189906821717 is 717128609981.

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 189906821717 - 2³⁴ = 172726952533 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 (189906821719) 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, 5199884 + ... + 5236277.

It is an arithmetic number, because the mean of its divisors is an integer number (24545853024).

Almost surely, 2^189906821717 is an apocalyptic number.

It is an amenable number.

189906821717 is a deficient number, since it is larger than the sum of its proper divisors (6460002475).

189906821717 is a wasteful number, since it uses less digits than its factorization.

189906821717 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10436779.

The product of its (nonzero) digits is 3048192, while the sum is 59.

The spelling of 189906821717 in words is "one hundred eighty-nine billion, nine hundred six million, eight hundred twenty-one thousand, seven hundred seventeen".