4991023 has 4 divisors (see below), whose sum is σ = 5208048. Its totient is φ = 4774000.

The previous prime is 4991011. The next prime is 4991029. The reversal of 4991023 is 3201994.

It is a happy number.

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-4991023 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 4990982 and 4991000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4991029) 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, 108478 + ... + 108523.

It is an arithmetic number, because the mean of its divisors is an integer number (1302012).

Almost surely, 2^4991023 is an apocalyptic number.

4991023 is a deficient number, since it is larger than the sum of its proper divisors (217025).

4991023 is a wasteful number, since it uses less digits than its factorization.

4991023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 217024.

The product of its (nonzero) digits is 1944, while the sum is 28.

The square root of 4991023 is about 2234.0597574819. The cubic root of 4991023 is about 170.8951970011.

The spelling of 4991023 in words is "four million, nine hundred ninety-one thousand, twenty-three".