66581055 has 16 divisors (see below), whose sum is σ = 118366560. Its totient is φ = 35509824.

The previous prime is 66581051. The next prime is 66581059. The reversal of 66581055 is 55018566.

It is an interprime number because it is at equal distance from previous prime (66581051) and next prime (66581059).

It is not a de Polignac number, because 66581055 - 2² = 66581051 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66581051) 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, 246462 + ... + 246731.

It is an arithmetic number, because the mean of its divisors is an integer number (7397910).

Almost surely, 2^66581055 is an apocalyptic number.

66581055 is a deficient number, since it is larger than the sum of its proper divisors (51785505).

66581055 is a wasteful number, since it uses less digits than its factorization.

66581055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 493207 (or 493201 counting only the distinct ones).

The product of its (nonzero) digits is 36000, while the sum is 36.

The square root of 66581055 is about 8159.7215026004. The cubic root of 66581055 is about 405.3064895375.

The spelling of 66581055 in words is "sixty-six million, five hundred eighty-one thousand, fifty-five".