891980923 has 4 divisors (see below), whose sum is σ = 892049320. Its totient is φ = 891912528.

The previous prime is 891980861. The next prime is 891980989. The reversal of 891980923 is 329089198.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-891980923 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (891983923) 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, 7890 + ... + 42967.

It is an arithmetic number, because the mean of its divisors is an integer number (223012330).

Almost surely, 2^891980923 is an apocalyptic number.

891980923 is a deficient number, since it is larger than the sum of its proper divisors (68397).

891980923 is a wasteful number, since it uses less digits than its factorization.

891980923 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68396.

The product of its (nonzero) digits is 279936, while the sum is 49.

The square root of 891980923 is about 29866.0496718264. The cubic root of 891980923 is about 962.6132945403.

The spelling of 891980923 in words is "eight hundred ninety-one million, nine hundred eighty thousand, nine hundred twenty-three".