5221991 has 4 divisors (see below), whose sum is σ = 5245632. Its totient is φ = 5198352.

The previous prime is 5221987. The next prime is 5222011. The reversal of 5221991 is 1991225.

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 5221991 - 2² = 5221987 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5221291) 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, 11486 + ... + 11931.

It is an arithmetic number, because the mean of its divisors is an integer number (1311408).

Almost surely, 2^5221991 is an apocalyptic number.

5221991 is a deficient number, since it is larger than the sum of its proper divisors (23641).

5221991 is a wasteful number, since it uses less digits than its factorization.

5221991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23640.

The product of its digits is 1620, while the sum is 29.

The square root of 5221991 is about 2285.1676087325. The cubic root of 5221991 is about 173.4917014969.

The spelling of 5221991 in words is "five million, two hundred twenty-one thousand, nine hundred ninety-one".