521169213792401 has 2 divisors, whose sum is σ = 521169213792402. Its totient is φ = 521169213792400.

The previous prime is 521169213792361. The next prime is 521169213792467. The reversal of 521169213792401 is 104297312961125.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 451774982490001 + 69394231302400 = 21254999^2 + 8330320^2 .

It is a cyclic number.

It is not a de Polignac number, because 521169213792401 - 2¹⁸ = 521169213530257 is a prime.

It is not a weakly prime, because it can be changed into another prime (521169213792301) 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, 260584606896200 + 260584606896201.

It is an arithmetic number, because the mean of its divisors is an integer number (260584606896201).

Almost surely, 2^{521169213792401} is an apocalyptic number.

It is an amenable number.

521169213792401 is a deficient number, since it is larger than the sum of its proper divisors (1).

521169213792401 is an equidigital number, since it uses as much as digits as its factorization.

521169213792401 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1632960, while the sum is 53.

The spelling of 521169213792401 in words is "five hundred twenty-one trillion, one hundred sixty-nine billion, two hundred thirteen million, seven hundred ninety-two thousand, four hundred one".