66220150621 has 4 divisors (see below), whose sum is σ = 68356284544. Its totient is φ = 64084016700.

The previous prime is 66220150603. The next prime is 66220150699. The reversal of 66220150621 is 12605102266.

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 66220150621 - 2¹⁷ = 66220019549 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (31), and also a Moran number because the ratio is a prime number: 2136133891 = 66220150621 / (6 + 6 + 2 + 2 + 0 + 1 + 5 + 0 + 6 + 2 + 1).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66220150421) 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, 1068066915 + ... + 1068066976.

It is an arithmetic number, because the mean of its divisors is an integer number (17089071136).

Almost surely, 2^66220150621 is an apocalyptic number.

It is an amenable number.

66220150621 is a deficient number, since it is larger than the sum of its proper divisors (2136133923).

66220150621 is a wasteful number, since it uses less digits than its factorization.

66220150621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2136133922.

The product of its (nonzero) digits is 8640, while the sum is 31.

Adding to 66220150621 its reverse (12605102266), we get a palindrome (78825252887).

The spelling of 66220150621 in words is "sixty-six billion, two hundred twenty million, one hundred fifty thousand, six hundred twenty-one".