190821131909 has 8 divisors (see below), whose sum is σ = 195541940160. Its totient is φ = 186103496800.

The previous prime is 190821131903. The next prime is 190821131951. The reversal of 190821131909 is 909131128091.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-190821131909 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 190821131909.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (190821131903) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 671297 + ... + 912294.

It is an arithmetic number, because the mean of its divisors is an integer number (24442742520).

Almost surely, 2^190821131909 is an apocalyptic number.

It is an amenable number.

190821131909 is a deficient number, since it is larger than the sum of its proper divisors (4720808251).

190821131909 is a wasteful number, since it uses less digits than its factorization.

190821131909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1586571.

The product of its (nonzero) digits is 34992, while the sum is 44.

The spelling of 190821131909 in words is "one hundred ninety billion, eight hundred twenty-one million, one hundred thirty-one thousand, nine hundred nine".