6523991 has 4 divisors (see below), whose sum is σ = 6621432. Its totient is φ = 6426552.

The previous prime is 6523969. The next prime is 6524009. The reversal of 6523991 is 1993256.

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 6523991 - 2²² = 2329687 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 (6523091) 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, 48620 + ... + 48753.

It is an arithmetic number, because the mean of its divisors is an integer number (1655358).

Almost surely, 2^6523991 is an apocalyptic number.

6523991 is a deficient number, since it is larger than the sum of its proper divisors (97441).

6523991 is an equidigital number, since it uses as much as digits as its factorization.

6523991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97440.

The product of its digits is 14580, while the sum is 35.

The square root of 6523991 is about 2554.2104455193. The cubic root of 6523991 is about 186.8548827910.

The spelling of 6523991 in words is "six million, five hundred twenty-three thousand, nine hundred ninety-one".