87856781392 has 20 divisors (see below), whose sum is σ = 170837044276. Its totient is φ = 43769802240.

The previous prime is 87856781329. The next prime is 87856781393. The reversal of 87856781392 is 29318765878.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 13805310016 + 74051471376 = 117496^2 + 272124^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87856781393) 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, 9907209 + ... + 9916072.

Almost surely, 2^87856781392 is an apocalyptic number.

It is an amenable number.

87856781392 is a deficient number, since it is larger than the sum of its proper divisors (82980262884).

87856781392 is a wasteful number, since it uses less digits than its factorization.

87856781392 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19823566 (or 19823560 counting only the distinct ones).

The product of its digits is 40642560, while the sum is 64.

It can be divided in two parts, 878567 and 81392, that added together give a palindrome (959959).

The spelling of 87856781392 in words is "eighty-seven billion, eight hundred fifty-six million, seven hundred eighty-one thousand, three hundred ninety-two".