78017640479 has 4 divisors (see below), whose sum is σ = 78049139784. Its totient is φ = 77986141176.

The previous prime is 78017640469. The next prime is 78017640499. The reversal of 78017640479 is 97404671087.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 78017640479 - 2⁸ = 78017640223 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 78017640479.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78017640469) 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, 15745937 + ... + 15750890.

It is an arithmetic number, because the mean of its divisors is an integer number (19512284946).

Almost surely, 2^78017640479 is an apocalyptic number.

78017640479 is a deficient number, since it is larger than the sum of its proper divisors (31499305).

78017640479 is a wasteful number, since it uses less digits than its factorization.

78017640479 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31499304.

The product of its (nonzero) digits is 2370816, while the sum is 53.

The spelling of 78017640479 in words is "seventy-eight billion, seventeen million, six hundred forty thousand, four hundred seventy-nine".