666655552 has 56 divisors (see below), whose sum is σ = 1394130816. Its totient is φ = 315667968.

The previous prime is 666655547. The next prime is 666655559. The reversal of 666655552 is 255556666.

666655552 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (46).

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666655559) 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, 149418 + ... + 153814.

Almost surely, 2^666655552 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 666655552, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (697065408).

666655552 is an abundant number, since it is smaller than the sum of its proper divisors (727475264).

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

666655552 is a wasteful number, since it uses less digits than its factorization.

666655552 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4535 (or 4525 counting only the distinct ones).

The product of its digits is 1620000, while the sum is 46.

The square root of 666655552 is about 25819.6737392245. The cubic root of 666655552 is about 873.5756099315.

The spelling of 666655552 in words is "six hundred sixty-six million, six hundred fifty-five thousand, five hundred fifty-two".