4815991 has 4 divisors (see below), whose sum is σ = 4820584. Its totient is φ = 4811400.

The previous prime is 4815989. The next prime is 4815997. The reversal of 4815991 is 1995184.

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 a cyclic number.

It is not a de Polignac number, because 4815991 - 2¹ = 4815989 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 4815991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4815997) 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, 136 + ... + 3106.

It is an arithmetic number, because the mean of its divisors is an integer number (1205146).

Almost surely, 2^4815991 is an apocalyptic number.

4815991 is a deficient number, since it is larger than the sum of its proper divisors (4593).

4815991 is a wasteful number, since it uses less digits than its factorization.

4815991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4592.

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

The square root of 4815991 is about 2194.5366253494. The cubic root of 4815991 is about 168.8736494758.

The spelling of 4815991 in words is "four million, eight hundred fifteen thousand, nine hundred ninety-one".