861720563 has 8 divisors (see below), whose sum is σ = 942205440. Its totient is φ = 781593480.

The previous prime is 861720487. The next prime is 861720569. The reversal of 861720563 is 365027168.

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

It is a cyclic number.

It is not a de Polignac number, because 861720563 - 2¹⁰ = 861719539 is a prime.

It is not an unprimeable number, because it can be changed into a prime (861720569) 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, 84395 + ... + 94052.

It is an arithmetic number, because the mean of its divisors is an integer number (117775680).

Almost surely, 2^861720563 is an apocalyptic number.

861720563 is a deficient number, since it is larger than the sum of its proper divisors (80484877).

861720563 is a wasteful number, since it uses less digits than its factorization.

861720563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 178897.

The product of its (nonzero) digits is 60480, while the sum is 38.

The square root of 861720563 is about 29355.0772950779. The cubic root of 861720563 is about 951.6023053909.

The spelling of 861720563 in words is "eight hundred sixty-one million, seven hundred twenty thousand, five hundred sixty-three".