4991221994 has 16 divisors (see below), whose sum is σ = 8259226560. Its totient is φ = 2243244960.

The previous prime is 4991221993. The next prime is 4991222021.

4991221994 is nontrivially palindromic in base 10.

It is not an unprimeable number, because it can be changed into a prime (4991221993) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1272614 + ... + 1276529.

It is an arithmetic number, because the mean of its divisors is an integer number (516201660).

Almost surely, 2^4991221994 is an apocalyptic number.

4991221994 is a deficient number, since it is larger than the sum of its proper divisors (3268004566).

4991221994 is a wasteful number, since it uses less digits than its factorization.

4991221994 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2549245.

The product of its digits is 419904, while the sum is 50.

The square root of 4991221994 is about 70648.5809765490. The cubic root of 4991221994 is about 1708.9746818994.

The spelling of 4991221994 in words is "four billion, nine hundred ninety-one million, two hundred twenty-one thousand, nine hundred ninety-four".