6669591 has 4 divisors (see below), whose sum is σ = 8892792. Its totient is φ = 4446392.

The previous prime is 6669587. The next prime is 6669617. The reversal of 6669591 is 1959666.

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 6669591 - 2² = 6669587 is a prime.

It is a D-number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6669521) 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, 1111596 + ... + 1111601.

It is an arithmetic number, because the mean of its divisors is an integer number (2223198).

Almost surely, 2^6669591 is an apocalyptic number.

6669591 is a deficient number, since it is larger than the sum of its proper divisors (2223201).

6669591 is a wasteful number, since it uses less digits than its factorization.

6669591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2223200.

The product of its digits is 87480, while the sum is 42.

The square root of 6669591 is about 2582.5551300989. Note that the first 3 decimals coincide. The cubic root of 6669591 is about 188.2347207837.

It can be divided in two parts, 6669 and 591, that added together give a triangular number (7260 = T₁₂₀).

The spelling of 6669591 in words is "six million, six hundred sixty-nine thousand, five hundred ninety-one".