189920721485 has 16 divisors (see below), whose sum is σ = 248653737792. Its totient is φ = 138107356800.

The previous prime is 189920721451. The next prime is 189920721491. The reversal of 189920721485 is 584127029981.

It is not a de Polignac number, because 189920721485 - 2⁸ = 189920721229 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 189920721485.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 255425 + ... + 667145.

It is an arithmetic number, because the mean of its divisors is an integer number (15540858612).

Almost surely, 2^189920721485 is an apocalyptic number.

It is an amenable number.

189920721485 is a deficient number, since it is larger than the sum of its proper divisors (58733016307).

189920721485 is a wasteful number, since it uses less digits than its factorization.

189920721485 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 420124.

The product of its (nonzero) digits is 2903040, while the sum is 56.

The spelling of 189920721485 in words is "one hundred eighty-nine billion, nine hundred twenty million, seven hundred twenty-one thousand, four hundred eighty-five".