869785128 has 40 divisors (see below), whose sum is σ = 2436205530. Its totient is φ = 289928160.

The previous prime is 869785117. The next prime is 869785171. The reversal of 869785128 is 821587968.

It can be written as a sum of positive squares in only one way, i.e., 682149924 + 187635204 = 26118^2 + 13698^2 .

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 670483 + ... + 671778.

Almost surely, 2^869785128 is an apocalyptic number.

It is an amenable number.

869785128 is an abundant number, since it is smaller than the sum of its proper divisors (1566420402).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

869785128 is a wasteful number, since it uses less digits than its factorization.

869785128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1342279 (or 1342266 counting only the distinct ones).

The product of its digits is 1935360, while the sum is 54.

The square root of 869785128 is about 29492.1197610480. The cubic root of 869785128 is about 954.5616723330.

The spelling of 869785128 in words is "eight hundred sixty-nine million, seven hundred eighty-five thousand, one hundred twenty-eight".