78231515750581 has 4 divisors (see below), whose sum is σ = 82348963948000. Its totient is φ = 74114067553164.

The previous prime is 78231515750569. The next prime is 78231515750603. The reversal of 78231515750581 is 18505751513287.

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.

It is a cyclic number.

It is not a de Polignac number, because 78231515750581 - 2⁴⁵ = 43047143661749 is a prime.

It is a super-2 number, since 2×78231515750581² (a number of 29 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 (78231515720581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2058724098681 + ... + 2058724098718.

It is an arithmetic number, because the mean of its divisors is an integer number (20587240987000).

Almost surely, 2^{78231515750581} is an apocalyptic number.

It is an amenable number.

78231515750581 is a deficient number, since it is larger than the sum of its proper divisors (4117448197419).

78231515750581 is a wasteful number, since it uses less digits than its factorization.

78231515750581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4117448197418.

The product of its (nonzero) digits is 11760000, while the sum is 58.

The spelling of 78231515750581 in words is "seventy-eight trillion, two hundred thirty-one billion, five hundred fifteen million, seven hundred fifty thousand, five hundred eighty-one".