3666792721 has 2 divisors, whose sum is σ = 3666792722. Its totient is φ = 3666792720.

The previous prime is 3666792677. The next prime is 3666792769. The reversal of 3666792721 is 1272976663.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3207976321 + 458816400 = 56639^2 + 21420^2 .

It is a cyclic number.

It is not a de Polignac number, because 3666792721 - 2²¹ = 3664695569 is a prime.

It is not a weakly prime, because it can be changed into another prime (3666795721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1833396360 + 1833396361.

It is an arithmetic number, because the mean of its divisors is an integer number (1833396361).

Almost surely, 2^3666792721 is an apocalyptic number.

It is an amenable number.

3666792721 is a deficient number, since it is larger than the sum of its proper divisors (1).

3666792721 is an equidigital number, since it uses as much as digits as its factorization.

3666792721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1143072, while the sum is 49.

The square root of 3666792721 is about 60554.0479324050. The cubic root of 3666792721 is about 1542.0393402990.

The spelling of 3666792721 in words is "three billion, six hundred sixty-six million, seven hundred ninety-two thousand, seven hundred twenty-one".