66621012 has 24 divisors (see below), whose sum is σ = 155586816. Its totient is φ = 22187328.

The previous prime is 66621007. The next prime is 66621017. The reversal of 66621012 is 21012666.

66621012 is digitally balanced in base 9, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (66621007) and next prime (66621017).

66621012 is strictly pandigital in base 9.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66621017) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19453 + ... + 22619.

It is an arithmetic number, because the mean of its divisors is an integer number (6482784).

Almost surely, 2^66621012 is an apocalyptic number.

It is an amenable number.

66621012 is an abundant number, since it is smaller than the sum of its proper divisors (88965804).

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

66621012 is a wasteful number, since it uses less digits than its factorization.

66621012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4927 (or 4925 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 66621012 is about 8162.1695645214. The cubic root of 66621012 is about 405.3875515996.

Adding to 66621012 its reverse (21012666), we get a palindrome (87633678).

The spelling of 66621012 in words is "sixty-six million, six hundred twenty-one thousand, twelve".