861289065 has 96 divisors (see below), whose sum is σ = 1895235840. Its totient is φ = 363377664.

The previous prime is 861289063. The next prime is 861289069. The reversal of 861289065 is 560982168.

It is not a de Polignac number, because 861289065 - 2¹ = 861289063 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 861289065.

It is not an unprimeable number, because it can be changed into a prime (861289063) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 157009 + ... + 162401.

It is an arithmetic number, because the mean of its divisors is an integer number (19742040).

Almost surely, 2^861289065 is an apocalyptic number.

It is an amenable number.

861289065 is an abundant number, since it is smaller than the sum of its proper divisors (1033946775).

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

861289065 is a wasteful number, since it uses less digits than its factorization.

861289065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5440 (or 5421 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 45.

The square root of 861289065 is about 29347.7267433101. The cubic root of 861289065 is about 951.4434437424.

The spelling of 861289065 in words is "eight hundred sixty-one million, two hundred eighty-nine thousand, sixty-five".