78531121358287 has 4 divisors (see below), whose sum is σ = 84571976847400. Its totient is φ = 72490265869176.

The previous prime is 78531121358197. The next prime is 78531121358293. The reversal of 78531121358287 is 78285312113587.

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 78531121358287 - 2⁷ = 78531121358159 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78531121358387) 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, 3020427744537 + ... + 3020427744562.

It is an arithmetic number, because the mean of its divisors is an integer number (21142994211850).

Almost surely, 2^{78531121358287} is an apocalyptic number.

78531121358287 is a deficient number, since it is larger than the sum of its proper divisors (6040855489113).

78531121358287 is a wasteful number, since it uses less digits than its factorization.

78531121358287 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6040855489112.

The product of its digits is 22579200, while the sum is 61.

The spelling of 78531121358287 in words is "seventy-eight trillion, five hundred thirty-one billion, one hundred twenty-one million, three hundred fifty-eight thousand, two hundred eighty-seven".