666784552 has 24 divisors (see below), whose sum is σ = 1454339610. Its totient is φ = 285764640.

The previous prime is 666784541. The next prime is 666784571. The reversal of 666784552 is 255487666.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 594091876 + 72692676 = 24374^2 + 8526^2 .

It is a Harshad number since it is a multiple of its sum of digits (49).

It is a junction number, because it is equal to n+sod(n) for n = 666784496 and 666784505.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 850099 + ... + 850882.

Almost surely, 2^666784552 is an apocalyptic number.

It is an amenable number.

666784552 is an abundant number, since it is smaller than the sum of its proper divisors (787555058).

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

666784552 is a wasteful number, since it uses less digits than its factorization.

666784552 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1701001 (or 1700990 counting only the distinct ones).

The product of its digits is 2419200, while the sum is 49.

The square root of 666784552 is about 25822.1717134714. The cubic root of 666784552 is about 873.6319528637.

It can be divided in two parts, 6667 and 84552, that added together give a palindrome (91219).

The spelling of 666784552 in words is "six hundred sixty-six million, seven hundred eighty-four thousand, five hundred fifty-two".