861826729 has 4 divisors (see below), whose sum is σ = 862337476. Its totient is φ = 861315984.

The previous prime is 861826723. The next prime is 861826739. The reversal of 861826729 is 927628168.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 94536729 + 767290000 = 9723^2 + 27700^2 .

It is a cyclic number.

It is not a de Polignac number, because 861826729 - 2¹¹ = 861824681 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (861826723) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 252834 + ... + 256219.

It is an arithmetic number, because the mean of its divisors is an integer number (215584369).

Almost surely, 2^861826729 is an apocalyptic number.

It is an amenable number.

861826729 is a deficient number, since it is larger than the sum of its proper divisors (510747).

861826729 is a wasteful number, since it uses less digits than its factorization.

861826729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 510746.

The product of its digits is 580608, while the sum is 49.

The square root of 861826729 is about 29356.8855466652. The cubic root of 861826729 is about 951.6413836668.

The spelling of 861826729 in words is "eight hundred sixty-one million, eight hundred twenty-six thousand, seven hundred twenty-nine".