1285185173 has 2 divisors, whose sum is σ = 1285185174. Its totient is φ = 1285185172.

The previous prime is 1285185169. The next prime is 1285185179. The reversal of 1285185173 is 3715815821.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1235030449 + 50154724 = 35143^2 + 7082^2 .

It is an emirp because it is prime and its reverse (3715815821) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1285185173 - 2² = 1285185169 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1285185173.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1285185179) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 642592586 + 642592587.

It is an arithmetic number, because the mean of its divisors is an integer number (642592587).

Almost surely, 2^1285185173 is an apocalyptic number.

It is an amenable number.

1285185173 is a deficient number, since it is larger than the sum of its proper divisors (1).

1285185173 is an equidigital number, since it uses as much as digits as its factorization.

1285185173 is an evil number, because the sum of its binary digits is even.

The product of its digits is 67200, while the sum is 41.

The square root of 1285185173 is about 35849.4793964989. The cubic root of 1285185173 is about 1087.2311885561.

The spelling of 1285185173 in words is "one billion, two hundred eighty-five million, one hundred eighty-five thousand, one hundred seventy-three".