6815815380 has 72 divisors (see below), whose sum is σ = 22554159264. Its totient is φ = 1652318400.

The previous prime is 6815815379. The next prime is 6815815417. The reversal of 6815815380 is 835185186.

6815815380 is a `hidden beast` number, since 68 + 1 + 58 + 1 + 538 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1719186 + ... + 1723145.

It is an arithmetic number, because the mean of its divisors is an integer number (313252212).

Almost surely, 2^6815815380 is an apocalyptic number.

6815815380 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

6815815380 is an abundant number, since it is smaller than the sum of its proper divisors (15738343884).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6815815380 is a wasteful number, since it uses less digits than its factorization.

6815815380 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3442357 (or 3442352 counting only the distinct ones).

The product of its (nonzero) digits is 230400, while the sum is 45.

The square root of 6815815380 is about 82557.9516461013. The cubic root of 6815815380 is about 1896.0041025655.

It can be divided in two parts, 68158 and 15380, that added together give a palindrome (83538).

The spelling of 6815815380 in words is "six billion, eight hundred fifteen million, eight hundred fifteen thousand, three hundred eighty".