4991851 has 8 divisors (see below), whose sum is σ = 5483520. Its totient is φ = 4523112.

The previous prime is 4991849. The next prime is 4991867. The reversal of 4991851 is 1581994.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 4991851 - 2¹ = 4991849 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 4991851.

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 7 ways as a sum of consecutive naturals, for example, 5275 + ... + 6148.

It is an arithmetic number, because the mean of its divisors is an integer number (685440).

Almost surely, 2^4991851 is an apocalyptic number.

4991851 is a deficient number, since it is larger than the sum of its proper divisors (491669).

4991851 is a wasteful number, since it uses less digits than its factorization.

4991851 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11465.

The product of its digits is 12960, while the sum is 37.

The square root of 4991851 is about 2234.2450626554. The cubic root of 4991851 is about 170.9046468607.

The spelling of 4991851 in words is "four million, nine hundred ninety-one thousand, eight hundred fifty-one".