66600621049 has 2 divisors, whose sum is σ = 66600621050. Its totient is φ = 66600621048.

The previous prime is 66600621029. The next prime is 66600621067. The reversal of 66600621049 is 94012600666.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 62578524649 + 4022096400 = 250157^2 + 63420^2 .

It is a cyclic number.

It is not a de Polignac number, because 66600621049 - 2¹³ = 66600612857 is a prime.

It is a super-2 number, since 2×66600621049² (a number of 22 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (66600621029) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33300310524 + 33300310525.

It is an arithmetic number, because the mean of its divisors is an integer number (33300310525).

Almost surely, 2^66600621049 is an apocalyptic number.

It is an amenable number.

66600621049 is a deficient number, since it is larger than the sum of its proper divisors (1).

66600621049 is an equidigital number, since it uses as much as digits as its factorization.

66600621049 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 93312, while the sum is 40.

The spelling of 66600621049 in words is "sixty-six billion, six hundred million, six hundred twenty-one thousand, forty-nine".