1389121997173 has 2 divisors, whose sum is σ = 1389121997174. Its totient is φ = 1389121997172.

The previous prime is 1389121997143. The next prime is 1389121997209. The reversal of 1389121997173 is 3717991219831.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1269446129809 + 119675867364 = 1126697^2 + 345942^2 .

It is a cyclic number.

It is not a de Polignac number, because 1389121997173 - 2²⁹ = 1388585126261 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1389121997143) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 694560998586 + 694560998587.

It is an arithmetic number, because the mean of its divisors is an integer number (694560998587).

Almost surely, 2^{1389121997173} is an apocalyptic number.

It is an amenable number.

1389121997173 is a deficient number, since it is larger than the sum of its proper divisors (1).

1389121997173 is an equidigital number, since it uses as much as digits as its factorization.

1389121997173 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5143824, while the sum is 61.

The spelling of 1389121997173 in words is "one trillion, three hundred eighty-nine billion, one hundred twenty-one million, nine hundred ninety-seven thousand, one hundred seventy-three".