4991779 has 4 divisors (see below), whose sum is σ = 5375776. Its totient is φ = 4607784.

The previous prime is 4991771. The next prime is 4991801. The reversal of 4991779 is 9771994.

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 4991779 - 2³ = 4991771 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (4991771) 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, 191979 + ... + 192004.

It is an arithmetic number, because the mean of its divisors is an integer number (1343944).

Almost surely, 2^4991779 is an apocalyptic number.

4991779 is a deficient number, since it is larger than the sum of its proper divisors (383997).

4991779 is a wasteful number, since it uses less digits than its factorization.

4991779 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 383996.

The product of its digits is 142884, while the sum is 46.

The square root of 4991779 is about 2234.2289497722. The cubic root of 4991779 is about 170.9038251752.

It can be divided in two parts, 499 and 1779, that added together give a triangular number (2278 = T₆₇).

The spelling of 4991779 in words is "four million, nine hundred ninety-one thousand, seven hundred seventy-nine".