66757620 has 48 divisors (see below), whose sum is σ = 191979648. Its totient is φ = 17320320.

The previous prime is 66757619. The next prime is 66757633. The reversal of 66757620 is 2675766.

It is a super-4 number, since 4×66757620⁴ (a number of 32 digits) contains 4444 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12816 + ... + 17255.

It is an arithmetic number, because the mean of its divisors is an integer number (3999576).

Almost surely, 2^66757620 is an apocalyptic number.

66757620 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

66757620 is an abundant number, since it is smaller than the sum of its proper divisors (125222028).

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

66757620 is a wasteful number, since it uses less digits than its factorization.

66757620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30120 (or 30118 counting only the distinct ones).

The product of its (nonzero) digits is 105840, while the sum is 39.

The square root of 66757620 is about 8170.5336423027. The cubic root of 66757620 is about 405.6644480918.

The spelling of 66757620 in words is "sixty-six million, seven hundred fifty-seven thousand, six hundred twenty".