4991887 has 4 divisors (see below), whose sum is σ = 4997376. Its totient is φ = 4986400.

The previous prime is 4991881. The next prime is 4991893. The reversal of 4991887 is 7881994.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is an interprime number because it is at equal distance from previous prime (4991881) and next prime (4991893).

It is a cyclic number.

It is not a de Polignac number, because 4991887 - 2³ = 4991879 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4991881) 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, 1018 + ... + 3319.

It is an arithmetic number, because the mean of its divisors is an integer number (1249344).

Almost surely, 2^4991887 is an apocalyptic number.

4991887 is a deficient number, since it is larger than the sum of its proper divisors (5489).

4991887 is a wasteful number, since it uses less digits than its factorization.

4991887 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5488.

The product of its digits is 145152, while the sum is 46.

The square root of 4991887 is about 2234.2531190534. The cubic root of 4991887 is about 170.9050577004.

It can be divided in two parts, 49918 and 87, that added together give a palindrome (50005).

The spelling of 4991887 in words is "four million, nine hundred ninety-one thousand, eight hundred eighty-seven".