1272781251 has 12 divisors (see below), whose sum is σ = 2101099312. Its totient is φ = 727303536.

The previous prime is 1272781249. The next prime is 1272781267. The reversal of 1272781251 is 1521872721.

It is not a de Polignac number, because 1272781251 - 2¹ = 1272781249 is a prime.

It is a super-2 number, since 2×1272781251² = 3239944225794250002, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1272781271) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10101376 + ... + 10101501.

Almost surely, 2^1272781251 is an apocalyptic number.

1272781251 is a deficient number, since it is larger than the sum of its proper divisors (828318061).

1272781251 is a wasteful number, since it uses less digits than its factorization.

1272781251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20202890 (or 20202887 counting only the distinct ones).

The product of its digits is 15680, while the sum is 36.

The square root of 1272781251 is about 35676.0599141777. The cubic root of 1272781251 is about 1083.7220829884.

The spelling of 1272781251 in words is "one billion, two hundred seventy-two million, seven hundred eighty-one thousand, two hundred fifty-one".