66211900 has 36 divisors (see below), whose sum is σ = 144209520. Its totient is φ = 26387200.

The previous prime is 66211867. The next prime is 66211913. The reversal of 66211900 is 911266.

66211900 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×66211900² = 8768031403220000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 30036 + ... + 32164.

It is an arithmetic number, because the mean of its divisors is an integer number (4005820).

Almost surely, 2^66211900 is an apocalyptic number.

It is an amenable number.

66211900 is an abundant number, since it is smaller than the sum of its proper divisors (77997620).

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

66211900 is a wasteful number, since it uses less digits than its factorization.

66211900 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2454 (or 2447 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 25.

The square root of 66211900 is about 8137.0694970610. The cubic root of 66211900 is about 404.5560343532.

The spelling of 66211900 in words is "sixty-six million, two hundred eleven thousand, nine hundred".