919811923 has 4 divisors (see below), whose sum is σ = 920486160. Its totient is φ = 919137688.

The previous prime is 919811903. The next prime is 919811951. The reversal of 919811923 is 329118919.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-919811923 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 919811923.

It is not an unprimeable number, because it can be changed into a prime (919811903) 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, 335068 + ... + 337801.

It is an arithmetic number, because the mean of its divisors is an integer number (230121540).

Almost surely, 2^919811923 is an apocalyptic number.

919811923 is a deficient number, since it is larger than the sum of its proper divisors (674237).

919811923 is a wasteful number, since it uses less digits than its factorization.

919811923 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 674236.

The product of its digits is 34992, while the sum is 43.

The square root of 919811923 is about 30328.4012602049. The cubic root of 919811923 is about 972.5225457641.

The spelling of 919811923 in words is "nine hundred nineteen million, eight hundred eleven thousand, nine hundred twenty-three".