866523553 has 16 divisors (see below), whose sum is σ = 1011159936. Its totient is φ = 727159680.

The previous prime is 866523533. The next prime is 866523571. The reversal of 866523553 is 355325668.

It is a cyclic number.

It is not a de Polignac number, because 866523553 - 2⁹ = 866523041 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (866523503) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 191050 + ... + 195532.

It is an arithmetic number, because the mean of its divisors is an integer number (63197496).

Almost surely, 2^866523553 is an apocalyptic number.

It is an amenable number.

866523553 is a deficient number, since it is larger than the sum of its proper divisors (144636383).

866523553 is a wasteful number, since it uses less digits than its factorization.

866523553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5064.

The product of its digits is 648000, while the sum is 43.

The square root of 866523553 is about 29436.7721226360. The cubic root of 866523553 is about 953.3670193513.

The spelling of 866523553 in words is "eight hundred sixty-six million, five hundred twenty-three thousand, five hundred fifty-three".