165663332460421 has 2 divisors, whose sum is σ = 165663332460422. Its totient is φ = 165663332460420.

The previous prime is 165663332460403. The next prime is 165663332460433. The reversal of 165663332460421 is 124064233366561.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 152573509764225 + 13089822696196 = 12352065^2 + 3617986^2 .

It is a cyclic number.

It is not a de Polignac number, because 165663332460421 - 2¹³ = 165663332452229 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (165663332490421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82831666230210 + 82831666230211.

It is an arithmetic number, because the mean of its divisors is an integer number (82831666230211).

Almost surely, 2^{165663332460421} is an apocalyptic number.

It is an amenable number.

165663332460421 is a deficient number, since it is larger than the sum of its proper divisors (1).

165663332460421 is an equidigital number, since it uses as much as digits as its factorization.

165663332460421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11197440, while the sum is 52.

The spelling of 165663332460421 in words is "one hundred sixty-five trillion, six hundred sixty-three billion, three hundred thirty-two million, four hundred sixty thousand, four hundred twenty-one".