6468991 has 4 divisors (see below), whose sum is σ = 6511984. Its totient is φ = 6426000.

The previous prime is 6468983. The next prime is 6468997. The reversal of 6468991 is 1998646.

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 6468991 - 2³ = 6468983 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 (6468997) 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, 21270 + ... + 21571.

It is an arithmetic number, because the mean of its divisors is an integer number (1627996).

Almost surely, 2^6468991 is an apocalyptic number.

6468991 is a deficient number, since it is larger than the sum of its proper divisors (42993).

6468991 is a wasteful number, since it uses less digits than its factorization.

6468991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42992.

The product of its digits is 93312, while the sum is 43.

The square root of 6468991 is about 2543.4211212459. The cubic root of 6468991 is about 186.3283117371.

The spelling of 6468991 in words is "six million, four hundred sixty-eight thousand, nine hundred ninety-one".