666199056 has 120 divisors (see below), whose sum is σ = 1804588864. Its totient is φ = 211703040.

The previous prime is 666199019. The next prime is 666199057. The reversal of 666199056 is 650991666.

It is a super-2 number, since 2×666199056² = 887642364430582272, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a junction number, because it is equal to n+sod(n) for n = 666198996 and 666199014.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666199057) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6467901 + ... + 6468003.

Almost surely, 2^666199056 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 666199056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (902294432).

666199056 is an abundant number, since it is smaller than the sum of its proper divisors (1138389808).

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

666199056 is a wasteful number, since it uses less digits than its factorization.

666199056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 269 (or 216 counting only the distinct ones).

The product of its (nonzero) digits is 524880, while the sum is 48.

The square root of 666199056 is about 25810.8321446636. The cubic root of 666199056 is about 873.3761691917.

The spelling of 666199056 in words is "six hundred sixty-six million, one hundred ninety-nine thousand, fifty-six".