1973065156421 has 2 divisors, whose sum is σ = 1973065156422. Its totient is φ = 1973065156420.

The previous prime is 1973065156357. The next prime is 1973065156423. The reversal of 1973065156421 is 1246515603791.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1581922485025 + 391142671396 = 1257745^2 + 625414^2 .

It is a cyclic number.

It is not a de Polignac number, because 1973065156421 - 2⁶ = 1973065156357 is a prime.

It is a super-2 number, since 2×1973065156421² (a number of 25 digits) contains 22 as substring.

Together with 1973065156423, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1973065156421.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1973065156423) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 986532578210 + 986532578211.

It is an arithmetic number, because the mean of its divisors is an integer number (986532578211).

Almost surely, 2^{1973065156421} is an apocalyptic number.

It is an amenable number.

1973065156421 is a deficient number, since it is larger than the sum of its proper divisors (1).

1973065156421 is an equidigital number, since it uses as much as digits as its factorization.

1973065156421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1360800, while the sum is 50.

The spelling of 1973065156421 in words is "one trillion, nine hundred seventy-three billion, sixty-five million, one hundred fifty-six thousand, four hundred twenty-one".