78287910381 has 6 divisors (see below), whose sum is σ = 113082537230. Its totient is φ = 52191940248.

The previous prime is 78287910377. The next prime is 78287910391. The reversal of 78287910381 is 18301978287.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 74360381481 + 3927528900 = 272691^2 + 62670^2 .

It is not a de Polignac number, because 78287910381 - 2² = 78287910377 is a prime.

It is a super-2 number, since 2×78287910381² (a number of 23 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 (78287910361) 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, 4349328346 + ... + 4349328363.

Almost surely, 2^78287910381 is an apocalyptic number.

It is an amenable number.

78287910381 is a deficient number, since it is larger than the sum of its proper divisors (34794626849).

78287910381 is a wasteful number, since it uses less digits than its factorization.

78287910381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8698656715 (or 8698656712 counting only the distinct ones).

The product of its (nonzero) digits is 1354752, while the sum is 54.

The spelling of 78287910381 in words is "seventy-eight billion, two hundred eighty-seven million, nine hundred ten thousand, three hundred eighty-one".