1281172397 has 8 divisors (see below), whose sum is σ = 1323684096. Its totient is φ = 1239075792.

The previous prime is 1281172307. The next prime is 1281172421. The reversal of 1281172397 is 7932711821.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1281172397 - 2²² = 1276978093 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1281172307) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 97493 + ... + 109850.

It is an arithmetic number, because the mean of its divisors is an integer number (165460512).

Almost surely, 2^1281172397 is an apocalyptic number.

It is an amenable number.

1281172397 is a deficient number, since it is larger than the sum of its proper divisors (42511699).

1281172397 is a wasteful number, since it uses less digits than its factorization.

1281172397 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 207547.

The product of its digits is 42336, while the sum is 41.

The square root of 1281172397 is about 35793.4686360515. The cubic root of 1281172397 is about 1086.0984428826.

The spelling of 1281172397 in words is "one billion, two hundred eighty-one million, one hundred seventy-two thousand, three hundred ninety-seven".