5155991 has 4 divisors (see below), whose sum is σ = 5166984. Its totient is φ = 5145000.

The previous prime is 5155961. The next prime is 5155993. The reversal of 5155991 is 1995515.

It is a happy number.

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 5155991 - 2²² = 961687 is a prime.

It is a super-4 number, since 4×5155991⁴ (a number of 28 digits) contains 4444 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5155993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4760 + ... + 5741.

It is an arithmetic number, because the mean of its divisors is an integer number (1291746).

Almost surely, 2^5155991 is an apocalyptic number.

5155991 is a deficient number, since it is larger than the sum of its proper divisors (10993).

5155991 is a wasteful number, since it uses less digits than its factorization.

5155991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10992.

The product of its digits is 10125, while the sum is 35.

The square root of 5155991 is about 2270.6807349339. The cubic root of 5155991 is about 172.7576880964.

The spelling of 5155991 in words is "five million, one hundred fifty-five thousand, nine hundred ninety-one".