816530047 has 4 divisors (see below), whose sum is σ = 836445456. Its totient is φ = 796614640.

The previous prime is 816529981. The next prime is 816530059. The reversal of 816530047 is 740035618.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-816530047 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 816529994 and 816530021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (816530347) 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, 9957643 + ... + 9957724.

It is an arithmetic number, because the mean of its divisors is an integer number (209111364).

Almost surely, 2^816530047 is an apocalyptic number.

816530047 is a deficient number, since it is larger than the sum of its proper divisors (19915409).

816530047 is a wasteful number, since it uses less digits than its factorization.

816530047 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19915408.

The product of its (nonzero) digits is 20160, while the sum is 34.

The square root of 816530047 is about 28574.9898862624. The cubic root of 816530047 is about 934.6680347061.

The spelling of 816530047 in words is "eight hundred sixteen million, five hundred thirty thousand, forty-seven".