861279804 has 480 divisors, whose sum is σ = 3122380800. Its totient is φ = 200154240.

The previous prime is 861279779. The next prime is 861279829. The reversal of 861279804 is 408972168.

861279804 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (861279779) and next prime (861279829).

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 861279804.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 10902237 + ... + 10902315.

It is an arithmetic number, because the mean of its divisors is an integer number (6504960).

Almost surely, 2^861279804 is an apocalyptic number.

861279804 is a gapful number since it is divisible by the number (84) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 861279804, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1561190400).

861279804 is an abundant number, since it is smaller than the sum of its proper divisors (2261100996).

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

861279804 is a wasteful number, since it uses less digits than its factorization.

861279804 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 155 (or 144 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 45.

The square root of 861279804 is about 29347.5689623519. The cubic root of 861279804 is about 951.4400336022.

The spelling of 861279804 in words is "eight hundred sixty-one million, two hundred seventy-nine thousand, eight hundred four".