78506653667751 has 24 divisors (see below), whose sum is σ = 114952962449520. Its totient is φ = 51620337991296.

The previous prime is 78506653667711. The next prime is 78506653667789. The reversal of 78506653667751 is 15776635660587.

It is a happy number.

78506653667751 is a `hidden beast` number, since 7 + 8 + 506 + 6 + 5 + 3 + 6 + 67 + 7 + 51 = 666.

It is not a de Polignac number, because 78506653667751 - 2¹⁷ = 78506653536679 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 78506653667751.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78506653667711) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 79761445 + ... + 80739713.

It is an arithmetic number, because the mean of its divisors is an integer number (4789706768730).

Almost surely, 2^{78506653667751} is an apocalyptic number.

78506653667751 is a deficient number, since it is larger than the sum of its proper divisors (36446308781769).

78506653667751 is a wasteful number, since it uses less digits than its factorization.

78506653667751 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1100495 (or 1100492 counting only the distinct ones).

The product of its (nonzero) digits is 1333584000, while the sum is 72.

It can be divided in two parts, 78506653 and 667751, that added together give a square (79174404 = 8898²).

The spelling of 78506653667751 in words is "seventy-eight trillion, five hundred six billion, six hundred fifty-three million, six hundred sixty-seven thousand, seven hundred fifty-one".