66425556 has 12 divisors (see below), whose sum is σ = 154992992. Its totient is φ = 22141848.

The previous prime is 66425551. The next prime is 66425561. The reversal of 66425556 is 65552466.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (66425551) and next prime (66425561).

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66425551) 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, 2767720 + ... + 2767743.

Almost surely, 2^66425556 is an apocalyptic number.

It is an amenable number.

66425556 is an abundant number, since it is smaller than the sum of its proper divisors (88567436).

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

66425556 is a wasteful number, since it uses less digits than its factorization.

66425556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5535470 (or 5535468 counting only the distinct ones).

The product of its digits is 216000, while the sum is 39.

The square root of 66425556 is about 8150.1874825062. The cubic root of 66425556 is about 404.9907146172.

The spelling of 66425556 in words is "sixty-six million, four hundred twenty-five thousand, five hundred fifty-six".