66100212 has 30 divisors (see below), whose sum is σ = 172799858. Its totient is φ = 22033296.

The previous prime is 66100207. The next prime is 66100261. The reversal of 66100212 is 21200166.

It is a happy number.

66100212 is a `hidden beast` number, since 661 + 0 + 0 + 2 + 1 + 2 = 666.

It can be written as a sum of positive squares in only one way, i.e., 63297936 + 2802276 = 7956^2 + 1674^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 101683 + ... + 102330.

Almost surely, 2^66100212 is an apocalyptic number.

It is an amenable number.

66100212 is an abundant number, since it is smaller than the sum of its proper divisors (106699646).

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

66100212 is a wasteful number, since it uses less digits than its factorization.

66100212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 204029 (or 204018 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 66100212 is about 8130.2036874853. The cubic root of 66100212 is about 404.3284343594.

Adding to 66100212 its reverse (21200166), we get a palindrome (87300378).

The spelling of 66100212 in words is "sixty-six million, one hundred thousand, two hundred twelve".