1273891385 has 36 divisors (see below), whose sum is σ = 1744954092. Its totient is φ = 887383296.

The previous prime is 1273891373. The next prime is 1273891403. The reversal of 1273891385 is 5831983721.

It can be written as a sum of positive squares in 6 ways, for example, as 387459856 + 886431529 = 19684^2 + 29773^2 .

It is not a de Polignac number, because 1273891385 - 2¹² = 1273887289 is a prime.

It is a Duffinian number.

Its product of digits (362880) is a multiple of the sum of its prime divisors (270).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 5467229 + ... + 5467461.

It is an arithmetic number, because the mean of its divisors is an integer number (48470947).

Almost surely, 2^1273891385 is an apocalyptic number.

It is an amenable number.

1273891385 is a deficient number, since it is larger than the sum of its proper divisors (471062707).

1273891385 is an equidigital number, since it uses as much as digits as its factorization.

1273891385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 522 (or 270 counting only the distinct ones).

The product of its digits is 362880, while the sum is 47.

The square root of 1273891385 is about 35691.6150517177. The cubic root of 1273891385 is about 1084.0370695896.

The spelling of 1273891385 in words is "one billion, two hundred seventy-three million, eight hundred ninety-one thousand, three hundred eighty-five".