3661838854721 has 2 divisors, whose sum is σ = 3661838854722. Its totient is φ = 3661838854720.

The previous prime is 3661838854703. The next prime is 3661838854847. The reversal of 3661838854721 is 1274588381663.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2329014784321 + 1332824070400 = 1526111^2 + 1154480^2 .

It is a cyclic number.

It is not a de Polignac number, because 3661838854721 - 2²⁶ = 3661771745857 is a prime.

It is not a weakly prime, because it can be changed into another prime (3661838854321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1830919427360 + 1830919427361.

It is an arithmetic number, because the mean of its divisors is an integer number (1830919427361).

Almost surely, 2^{3661838854721} is an apocalyptic number.

It is an amenable number.

3661838854721 is a deficient number, since it is larger than the sum of its proper divisors (1).

3661838854721 is an equidigital number, since it uses as much as digits as its factorization.

3661838854721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 46448640, while the sum is 62.

The spelling of 3661838854721 in words is "three trillion, six hundred sixty-one billion, eight hundred thirty-eight million, eight hundred fifty-four thousand, seven hundred twenty-one".