1272276391 has 4 divisors (see below), whose sum is σ = 1272589984. Its totient is φ = 1271962800.

The previous prime is 1272276367. The next prime is 1272276407. The reversal of 1272276391 is 1936722721.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1272276391 - 2⁷ = 1272276263 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 (1272276491) 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, 150630 + ... + 158851.

It is an arithmetic number, because the mean of its divisors is an integer number (318147496).

Almost surely, 2^1272276391 is an apocalyptic number.

1272276391 is a deficient number, since it is larger than the sum of its proper divisors (313593).

1272276391 is an equidigital number, since it uses as much as digits as its factorization.

1272276391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 313592.

The product of its digits is 63504, while the sum is 40.

The square root of 1272276391 is about 35668.9835992000. The cubic root of 1272276391 is about 1083.5787747052.

The spelling of 1272276391 in words is "one billion, two hundred seventy-two million, two hundred seventy-six thousand, three hundred ninety-one".