78609040381 has 4 divisors (see below), whose sum is σ = 78609967200. Its totient is φ = 78608113564.

The previous prime is 78609040361. The next prime is 78609040387. The reversal of 78609040381 is 18304090687.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18304090687 = 317 ⋅57741611.

It is a cyclic number.

It is not a de Polignac number, because 78609040381 - 2⁹ = 78609039869 is a prime.

It is a super-2 number, since 2×78609040381² (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 (78609040387) 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, 321751 + ... + 510628.

It is an arithmetic number, because the mean of its divisors is an integer number (19652491800).

Almost surely, 2^78609040381 is an apocalyptic number.

It is an amenable number.

78609040381 is a deficient number, since it is larger than the sum of its proper divisors (926819).

78609040381 is an equidigital number, since it uses as much as digits as its factorization.

78609040381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 926818.

The product of its (nonzero) digits is 290304, while the sum is 46.

The spelling of 78609040381 in words is "seventy-eight billion, six hundred nine million, forty thousand, three hundred eighty-one".