6442391 has 4 divisors (see below), whose sum is σ = 6463032. Its totient is φ = 6421752.

The previous prime is 6442367. The next prime is 6442399. The reversal of 6442391 is 1932446.

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 6442391 - 2²² = 2248087 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 (6442399) 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, 9845 + ... + 10478.

It is an arithmetic number, because the mean of its divisors is an integer number (1615758).

Almost surely, 2^6442391 is an apocalyptic number.

6442391 is a deficient number, since it is larger than the sum of its proper divisors (20641).

6442391 is a wasteful number, since it uses less digits than its factorization.

6442391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20640.

The product of its digits is 5184, while the sum is 29.

The square root of 6442391 is about 2538.1865573673. The cubic root of 6442391 is about 186.0725715963.

The spelling of 6442391 in words is "six million, four hundred forty-two thousand, three hundred ninety-one".