1269872521 has 2 divisors, whose sum is σ = 1269872522. Its totient is φ = 1269872520.

The previous prime is 1269872501. The next prime is 1269872567. The reversal of 1269872521 is 1252789621.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 926289225 + 343583296 = 30435^2 + 18536^2 .

It is an emirp because it is prime and its reverse (1252789621) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1269872521 - 2²⁵ = 1236318089 is a prime.

It is a super-2 number, since 2×1269872521² = 3225152439181790882, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1269872501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 634936260 + 634936261.

It is an arithmetic number, because the mean of its divisors is an integer number (634936261).

Almost surely, 2^1269872521 is an apocalyptic number.

It is an amenable number.

1269872521 is a deficient number, since it is larger than the sum of its proper divisors (1).

1269872521 is an equidigital number, since it uses as much as digits as its factorization.

1269872521 is an evil number, because the sum of its binary digits is even.

The product of its digits is 120960, while the sum is 43.

The square root of 1269872521 is about 35635.2707440255. The cubic root of 1269872521 is about 1082.8958977337.

The spelling of 1269872521 in words is "one billion, two hundred sixty-nine million, eight hundred seventy-two thousand, five hundred twenty-one".