78791081449 has 4 divisors (see below), whose sum is σ = 83425850964. Its totient is φ = 74156311936.

The previous prime is 78791081431. The next prime is 78791081477. The reversal of 78791081449 is 94418019787.

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 55539406224 + 23251675225 = 235668^2 + 152485^2 .

It is a cyclic number.

It is not a de Polignac number, because 78791081449 - 2²³ = 78782692841 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 78791081393 and 78791081402.

It is not an unprimeable number, because it can be changed into a prime (78791081849) 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, 2317384732 + ... + 2317384765.

It is an arithmetic number, because the mean of its divisors is an integer number (20856462741).

Almost surely, 2^78791081449 is an apocalyptic number.

It is an amenable number.

78791081449 is a deficient number, since it is larger than the sum of its proper divisors (4634769515).

78791081449 is a wasteful number, since it uses less digits than its factorization.

78791081449 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4634769514.

The product of its (nonzero) digits is 4064256, while the sum is 58.

The spelling of 78791081449 in words is "seventy-eight billion, seven hundred ninety-one million, eighty-one thousand, four hundred forty-nine".