854315815781 has 4 divisors (see below), whose sum is σ = 856446279564. Its totient is φ = 852185352000.

The previous prime is 854315815777. The next prime is 854315815783. The reversal of 854315815781 is 187518513458.

854315815781 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.

It can be written as a sum of positive squares in 2 ways, for example, as 842786425156 + 11529390625 = 918034^2 + 107375^2 .

It is a cyclic number.

It is not a de Polignac number, because 854315815781 - 2² = 854315815777 is a prime.

It is a super-2 number, since 2×854315815781² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (854315815783) 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, 1065231290 + ... + 1065232091.

It is an arithmetic number, because the mean of its divisors is an integer number (214111569891).

Almost surely, 2^854315815781 is an apocalyptic number.

It is an amenable number.

854315815781 is a deficient number, since it is larger than the sum of its proper divisors (2130463783).

854315815781 is a wasteful number, since it uses less digits than its factorization.

854315815781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2130463782.

The product of its digits is 5376000, while the sum is 56.

The spelling of 854315815781 in words is "eight hundred fifty-four billion, three hundred fifteen million, eight hundred fifteen thousand, seven hundred eighty-one".