820756665418 has 16 divisors (see below), whose sum is σ = 1248753888360. Its totient is φ = 404540856000.

The previous prime is 820756665367. The next prime is 820756665451. The reversal of 820756665418 is 814566657028.

It is a happy number.

820756665418 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 811247880249 + 9508785169 = 900693^2 + 97513^2 .

It is a super-2 number, since 2×820756665418² (a number of 25 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8825253 + ... + 8917768.

Almost surely, 2^820756665418 is an apocalyptic number.

820756665418 is a deficient number, since it is larger than the sum of its proper divisors (427997222942).

820756665418 is a wasteful number, since it uses less digits than its factorization.

820756665418 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17743353.

The product of its (nonzero) digits is 19353600, while the sum is 58.

The spelling of 820756665418 in words is "eight hundred twenty billion, seven hundred fifty-six million, six hundred sixty-five thousand, four hundred eighteen".