66214242120021 has 4 divisors (see below), whose sum is σ = 88285656160032. Its totient is φ = 44142828080012.

The previous prime is 66214242120017. The next prime is 66214242120041. The reversal of 66214242120021 is 12002124241266.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 66214242120021 - 2² = 66214242120017 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66214242120011) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11035707020001 + ... + 11035707020006.

It is an arithmetic number, because the mean of its divisors is an integer number (22071414040008).

Almost surely, 2^{66214242120021} is an apocalyptic number.

It is an amenable number.

66214242120021 is a deficient number, since it is larger than the sum of its proper divisors (22071414040011).

66214242120021 is a wasteful number, since it uses less digits than its factorization.

66214242120021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22071414040010.

The product of its (nonzero) digits is 18432, while the sum is 33.

Adding to 66214242120021 its reverse (12002124241266), we get a palindrome (78216366361287).

The spelling of 66214242120021 in words is "sixty-six trillion, two hundred fourteen billion, two hundred forty-two million, one hundred twenty thousand, twenty-one".