4491821881 has 4 divisors (see below), whose sum is σ = 4492307200. Its totient is φ = 4491336564.

The previous prime is 4491821857. The next prime is 4491821891. The reversal of 4491821881 is 1881281944.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 4491821881 - 2¹¹ = 4491819833 is a prime.

It is a super-2 number, since 2×4491821881² = 40352927621260756322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (4491821891) 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, 228501 + ... + 247378.

It is an arithmetic number, because the mean of its divisors is an integer number (1123076800).

Almost surely, 2^4491821881 is an apocalyptic number.

It is an amenable number.

4491821881 is a deficient number, since it is larger than the sum of its proper divisors (485319).

4491821881 is an equidigital number, since it uses as much as digits as its factorization.

4491821881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 485318.

The product of its digits is 147456, while the sum is 46.

The square root of 4491821881 is about 67021.0555049680. The cubic root of 4491821881 is about 1649.9628863400.

The spelling of 4491821881 in words is "four billion, four hundred ninety-one million, eight hundred twenty-one thousand, eight hundred eighty-one".