818220787 has 4 divisors (see below), whose sum is σ = 821616136. Its totient is φ = 814825440.

The previous prime is 818220763. The next prime is 818220803. The reversal of 818220787 is 787022818.

818220787 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 787022818 = 2 ⋅393511409.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-818220787 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (818220707) 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, 1697313 + ... + 1697794.

It is an arithmetic number, because the mean of its divisors is an integer number (205404034).

Almost surely, 2^818220787 is an apocalyptic number.

818220787 is a deficient number, since it is larger than the sum of its proper divisors (3395349).

818220787 is a wasteful number, since it uses less digits than its factorization.

818220787 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3395348.

The product of its (nonzero) digits is 100352, while the sum is 43.

The square root of 818220787 is about 28604.5588499456. The cubic root of 818220787 is about 935.3127103719.

The spelling of 818220787 in words is "eight hundred eighteen million, two hundred twenty thousand, seven hundred eighty-seven".