66821076 has 36 divisors (see below), whose sum is σ = 193039392. Its totient is φ = 19091664.

The previous prime is 66821071. The next prime is 66821093. The reversal of 66821076 is 67012866.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 66821076.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66821071) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 132330 + ... + 132833.

Almost surely, 2^66821076 is an apocalyptic number.

It is an amenable number.

66821076 is an abundant number, since it is smaller than the sum of its proper divisors (126218316).

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

66821076 is a wasteful number, since it uses less digits than its factorization.

66821076 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 265180 (or 265175 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 66821076 is about 8174.4159424389. The cubic root of 66821076 is about 405.7929412450.

The spelling of 66821076 in words is "sixty-six million, eight hundred twenty-one thousand, seventy-six".