78757512079509 has 24 divisors (see below), whose sum is σ = 122007665201760. Its totient is φ = 48803066069472.

The previous prime is 78757512079507. The next prime is 78757512079541. The reversal of 78757512079509 is 90597021575787.

78757512079509 is a `hidden beast` number, since 7 + 8 + 7 + 57 + 512 + 0 + 7 + 9 + 50 + 9 = 666.

It is not a de Polignac number, because 78757512079509 - 2¹ = 78757512079507 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (78757512079501) 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, 4344993259 + ... + 4345011384.

It is an arithmetic number, because the mean of its divisors is an integer number (5083652716740).

Almost surely, 2^{78757512079509} is an apocalyptic number.

It is an amenable number.

78757512079509 is a deficient number, since it is larger than the sum of its proper divisors (43250153122251).

78757512079509 is a wasteful number, since it uses less digits than its factorization.

78757512079509 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8690004721 (or 8690004718 counting only the distinct ones).

The product of its (nonzero) digits is 388962000, while the sum is 72.

The spelling of 78757512079509 in words is "seventy-eight trillion, seven hundred fifty-seven billion, five hundred twelve million, seventy-nine thousand, five hundred nine".