634878985 has 8 divisors (see below), whose sum is σ = 820459080. Its totient is φ = 468833664.

The previous prime is 634878983. The next prime is 634879001. The reversal of 634878985 is 589878436.

It can be written as a sum of positive squares in 4 ways, for example, as 24443136 + 610435849 = 4944^2 + 24707^2 .

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

It is not a de Polignac number, because 634878985 - 2¹ = 634878983 is a prime.

It is not an unprimeable number, because it can be changed into a prime (634878983) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4883620 + ... + 4883749.

It is an arithmetic number, because the mean of its divisors is an integer number (102557385).

Almost surely, 2^634878985 is an apocalyptic number.

634878985 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

634878985 is a deficient number, since it is larger than the sum of its proper divisors (185580095).

634878985 is a wasteful number, since it uses less digits than its factorization.

634878985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9767387.

The product of its digits is 11612160, while the sum is 58.

The square root of 634878985 is about 25196.8050554034. The cubic root of 634878985 is about 859.4691987717.

The spelling of 634878985 in words is "six hundred thirty-four million, eight hundred seventy-eight thousand, nine hundred eighty-five".