861140400777 has 6 divisors (see below), whose sum is σ = 1243869467802. Its totient is φ = 574093600512.

The previous prime is 861140400751. The next prime is 861140400787. The reversal of 861140400777 is 777004041168.

It can be written as a sum of positive squares in only one way, i.e., 852180074496 + 8960326281 = 923136^2 + 94659^2 .

It is not a de Polignac number, because 861140400777 - 2¹⁰ = 861140399753 is a prime.

It is not an unprimeable number, because it can be changed into a prime (861140400727) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 47841133368 + ... + 47841133385.

It is an arithmetic number, because the mean of its divisors is an integer number (207311577967).

Almost surely, 2^861140400777 is an apocalyptic number.

It is an amenable number.

861140400777 is a deficient number, since it is larger than the sum of its proper divisors (382729067025).

861140400777 is a wasteful number, since it uses less digits than its factorization.

861140400777 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95682266759 (or 95682266756 counting only the distinct ones).

The product of its (nonzero) digits is 263424, while the sum is 45.

The spelling of 861140400777 in words is "eight hundred sixty-one billion, one hundred forty million, four hundred thousand, seven hundred seventy-seven".