4991805 has 96 divisors (see below), whose sum is σ = 11321856. Its totient is φ = 1976832.

The previous prime is 4991803. The next prime is 4991839. The reversal of 4991805 is 5081994.

It is not a de Polignac number, because 4991805 - 2¹ = 4991803 is a prime.

4991805 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 4991805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4991801) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 94159 + ... + 94211.

It is an arithmetic number, because the mean of its divisors is an integer number (117936).

Almost surely, 2^4991805 is an apocalyptic number.

4991805 is a gapful number since it is divisible by the number (45) formed by its first and last digit.

It is an amenable number.

4991805 is an abundant number, since it is smaller than the sum of its proper divisors (6330051).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

4991805 is a wasteful number, since it uses less digits than its factorization.

4991805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107 (or 104 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The square root of 4991805 is about 2234.2347683267. The cubic root of 4991805 is about 170.9041218959.

It can be divided in two parts, 499 and 1805, that added together give a square (2304 = 48²).

The spelling of 4991805 in words is "four million, nine hundred ninety-one thousand, eight hundred five".