866204563 has 4 divisors (see below), whose sum is σ = 989948080. Its totient is φ = 742461048.

The previous prime is 866204539. The next prime is 866204569. The reversal of 866204563 is 365402668.

It is a happy number.

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

It is not a de Polignac number, because 866204563 - 2⁹ = 866204051 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (866204569) 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, 61871748 + ... + 61871761.

It is an arithmetic number, because the mean of its divisors is an integer number (247487020).

Almost surely, 2^866204563 is an apocalyptic number.

866204563 is a deficient number, since it is larger than the sum of its proper divisors (123743517).

866204563 is a wasteful number, since it uses less digits than its factorization.

866204563 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123743516.

The product of its (nonzero) digits is 207360, while the sum is 40.

The square root of 866204563 is about 29431.3534007527. The cubic root of 866204563 is about 953.2500185421.

The spelling of 866204563 in words is "eight hundred sixty-six million, two hundred four thousand, five hundred sixty-three".