6440291 has 16 divisors (see below), whose sum is σ = 7832160. Its totient is φ = 5214720.

The previous prime is 6440249. The next prime is 6440303. The reversal of 6440291 is 1920446.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6440291 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 6440291.

It is not an unprimeable number, because it can be changed into a prime (6440201) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3371 + ... + 4923.

It is an arithmetic number, because the mean of its divisors is an integer number (489510).

Almost surely, 2^6440291 is an apocalyptic number.

6440291 is a deficient number, since it is larger than the sum of its proper divisors (1391869).

6440291 is a wasteful number, since it uses less digits than its factorization.

6440291 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1606.

The product of its (nonzero) digits is 1728, while the sum is 26.

The square root of 6440291 is about 2537.7728424743. The cubic root of 6440291 is about 186.0523516259.

The spelling of 6440291 in words is "six million, four hundred forty thousand, two hundred ninety-one".