1272782281 has 4 divisors (see below), whose sum is σ = 1290708864. Its totient is φ = 1254855700.

The previous prime is 1272782267. The next prime is 1272782323. The reversal of 1272782281 is 1822872721.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1822872721 = 113 ⋅16131617.

It is a cyclic number.

It is not a de Polignac number, because 1272782281 - 2¹⁷ = 1272651209 is a prime.

It is a super-2 number, since 2×1272782281² = 3239949469655125922, which contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1272780281) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8963185 + ... + 8963326.

It is an arithmetic number, because the mean of its divisors is an integer number (322677216).

Almost surely, 2^1272782281 is an apocalyptic number.

It is an amenable number.

1272782281 is a deficient number, since it is larger than the sum of its proper divisors (17926583).

1272782281 is an equidigital number, since it uses as much as digits as its factorization.

1272782281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17926582.

The product of its digits is 50176, while the sum is 40.

The square root of 1272782281 is about 35676.0743496254. The cubic root of 1272782281 is about 1083.7223753228.

The spelling of 1272782281 in words is "one billion, two hundred seventy-two million, seven hundred eighty-two thousand, two hundred eighty-one".