291398491 has 4 divisors (see below), whose sum is σ = 291515800. Its totient is φ = 291281184.

The previous prime is 291398483. The next prime is 291398507. The reversal of 291398491 is 194893192.

It is a happy number.

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 291398491 - 2³ = 291398483 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (291398461) 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, 54846 + ... + 59923.

It is an arithmetic number, because the mean of its divisors is an integer number (72878950).

Almost surely, 2^291398491 is an apocalyptic number.

291398491 is a deficient number, since it is larger than the sum of its proper divisors (117309).

291398491 is a wasteful number, since it uses less digits than its factorization.

291398491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117308.

The product of its digits is 139968, while the sum is 46.

The square root of 291398491 is about 17070.3980914330. The cubic root of 291398491 is about 662.9728844524.

The spelling of 291398491 in words is "two hundred ninety-one million, three hundred ninety-eight thousand, four hundred ninety-one".