1673217273821 has 2 divisors, whose sum is σ = 1673217273822. Its totient is φ = 1673217273820.

The previous prime is 1673217273809. The next prime is 1673217273899. The reversal of 1673217273821 is 1283727123761.

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., 1238691091225 + 434526182596 = 1112965^2 + 659186^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1673217273821 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1673217273821.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1673217213821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 836608636910 + 836608636911.

It is an arithmetic number, because the mean of its divisors is an integer number (836608636911).

Almost surely, 2^{1673217273821} is an apocalyptic number.

It is an amenable number.

1673217273821 is a deficient number, since it is larger than the sum of its proper divisors (1).

1673217273821 is an equidigital number, since it uses as much as digits as its factorization.

1673217273821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1185408, while the sum is 50.

The spelling of 1673217273821 in words is "one trillion, six hundred seventy-three billion, two hundred seventeen million, two hundred seventy-three thousand, eight hundred twenty-one".