491223851 has 4 divisors (see below), whose sum is σ = 491547912. Its totient is φ = 490899792.

The previous prime is 491223847. The next prime is 491223893. The reversal of 491223851 is 158322194.

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

It is a cyclic number.

It is not a de Polignac number, because 491223851 - 2² = 491223847 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (491226851) 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, 159746 + ... + 162791.

It is an arithmetic number, because the mean of its divisors is an integer number (122886978).

Almost surely, 2^491223851 is an apocalyptic number.

491223851 is a deficient number, since it is larger than the sum of its proper divisors (324061).

491223851 is a wasteful number, since it uses less digits than its factorization.

491223851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 324060.

The product of its digits is 17280, while the sum is 35.

The square root of 491223851 is about 22163.5703576838. The cubic root of 491223851 is about 789.0293323242.

The spelling of 491223851 in words is "four hundred ninety-one million, two hundred twenty-three thousand, eight hundred fifty-one".