6819561438 has 16 divisors (see below), whose sum is σ = 13641302016. Its totient is φ = 2272823960.

The previous prime is 6819561421. The next prime is 6819561493. The reversal of 6819561438 is 8341659186.

It is a Curzon number.

It is a congruent number.

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, 48606 + ... + 126497.

It is an arithmetic number, because the mean of its divisors is an integer number (852581376).

Almost surely, 2^6819561438 is an apocalyptic number.

6819561438 is an abundant number, since it is smaller than the sum of its proper divisors (6821740578).

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

6819561438 is a wasteful number, since it uses less digits than its factorization.

6819561438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 181599.

The product of its digits is 1244160, while the sum is 51.

The square root of 6819561438 is about 82580.6359747853. The cubic root of 6819561438 is about 1896.3513948615.

The spelling of 6819561438 in words is "six billion, eight hundred nineteen million, five hundred sixty-one thousand, four hundred thirty-eight".