1291873385 has 32 divisors (see below), whose sum is σ = 1755316224. Its totient is φ = 904248000.

The previous prime is 1291873379. The next prime is 1291873391. The reversal of 1291873385 is 5833781921.

It is an interprime number because it is at equal distance from previous prime (1291873379) and next prime (1291873391).

It is not a de Polignac number, because 1291873385 - 2⁶ = 1291873321 is a prime.

It is a Smith number, since the sum of its digits (47) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 323672 + ... + 327638.

It is an arithmetic number, because the mean of its divisors is an integer number (54853632).

Almost surely, 2^1291873385 is an apocalyptic number.

It is an amenable number.

1291873385 is a deficient number, since it is larger than the sum of its proper divisors (463442839).

1291873385 is a wasteful number, since it uses less digits than its factorization.

1291873385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4205.

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

The square root of 1291873385 is about 35942.6402063065. The cubic root of 1291873385 is about 1089.1139405814.

The spelling of 1291873385 in words is "one billion, two hundred ninety-one million, eight hundred seventy-three thousand, three hundred eighty-five".