189910856903 has 4 divisors (see below), whose sum is σ = 189912516120. Its totient is φ = 189909197688.

The previous prime is 189910856893. The next prime is 189910856911. The reversal of 189910856903 is 309658019981.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 309658019981 = 91691 ⋅3377191.

It is a cyclic number.

It is not a de Polignac number, because 189910856903 - 2⁸ = 189910856647 is a prime.

It is a super-2 number, since 2×189910856903² (a number of 23 digits) 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 (189910856983) 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, 644093 + ... + 891446.

It is an arithmetic number, because the mean of its divisors is an integer number (47478129030).

Almost surely, 2^189910856903 is an apocalyptic number.

189910856903 is a deficient number, since it is larger than the sum of its proper divisors (1659217).

189910856903 is a wasteful number, since it uses less digits than its factorization.

189910856903 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1659216.

The product of its (nonzero) digits is 4199040, while the sum is 59.

The spelling of 189910856903 in words is "one hundred eighty-nine billion, nine hundred ten million, eight hundred fifty-six thousand, nine hundred three".