816747491 has 8 divisors (see below), whose sum is σ = 934166880. Its totient is φ = 699513408.

The previous prime is 816747479. The next prime is 816747497. The reversal of 816747491 is 194747618.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 816747491 - 2⁶ = 816747427 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (816747497) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36746 + ... + 54623.

It is an arithmetic number, because the mean of its divisors is an integer number (116770860).

Almost surely, 2^816747491 is an apocalyptic number.

816747491 is a deficient number, since it is larger than the sum of its proper divisors (117419389).

816747491 is a wasteful number, since it uses less digits than its factorization.

816747491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92653.

The product of its digits is 338688, while the sum is 47.

The square root of 816747491 is about 28578.7944287368. The cubic root of 816747491 is about 934.7509954898.

The spelling of 816747491 in words is "eight hundred sixteen million, seven hundred forty-seven thousand, four hundred ninety-one".