9129878785 has 8 divisors (see below), whose sum is σ = 10957498920. Its totient is φ = 7302806784.

The previous prime is 9129878753. The next prime is 9129878801. The reversal of 9129878785 is 5878789219.

It can be written as a sum of positive squares in 4 ways, for example, as 284664384 + 8845214401 = 16872^2 + 94049^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 9129878785 - 2⁵ = 9129878753 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 99450 + ... + 167779.

It is an arithmetic number, because the mean of its divisors is an integer number (1369687365).

Almost surely, 2^9129878785 is an apocalyptic number.

It is an amenable number.

9129878785 is a deficient number, since it is larger than the sum of its proper divisors (1827620135).

9129878785 is a wasteful number, since it uses less digits than its factorization.

9129878785 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 274067.

The product of its digits is 20321280, while the sum is 64.

The square root of 9129878785 is about 95550.3991880725. The cubic root of 9129878785 is about 2090.0419537071.

The spelling of 9129878785 in words is "nine billion, one hundred twenty-nine million, eight hundred seventy-eight thousand, seven hundred eighty-five".