6625591 has 4 divisors (see below), whose sum is σ = 7572112. Its totient is φ = 5679072.

The previous prime is 6625579. The next prime is 6625603. The reversal of 6625591 is 1955266.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (6625579) and next prime (6625603).

It is not a de Polignac number, because 6625591 - 2¹⁵ = 6592823 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 (6625501) 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, 473250 + ... + 473263.

It is an arithmetic number, because the mean of its divisors is an integer number (1893028).

Almost surely, 2^6625591 is an apocalyptic number.

6625591 is a deficient number, since it is larger than the sum of its proper divisors (946521).

6625591 is an equidigital number, since it uses as much as digits as its factorization.

6625591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 946520.

The product of its digits is 16200, while the sum is 34.

The square root of 6625591 is about 2574.0223386754. The cubic root of 6625591 is about 187.8198723623.

The spelling of 6625591 in words is "six million, six hundred twenty-five thousand, five hundred ninety-one".