1272003521 has 2 divisors, whose sum is σ = 1272003522. Its totient is φ = 1272003520.

The previous prime is 1272003503. The next prime is 1272003599. The reversal of 1272003521 is 1253002721.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1080042496 + 191961025 = 32864^2 + 13855^2 .

It is an emirp because it is prime and its reverse (1253002721) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1272003521 - 2⁶ = 1272003457 is a prime.

It is not a weakly prime, because it can be changed into another prime (1272003221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 636001760 + 636001761.

It is an arithmetic number, because the mean of its divisors is an integer number (636001761).

Almost surely, 2^1272003521 is an apocalyptic number.

It is an amenable number.

1272003521 is a deficient number, since it is larger than the sum of its proper divisors (1).

1272003521 is an equidigital number, since it uses as much as digits as its factorization.

1272003521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 840, while the sum is 23.

The square root of 1272003521 is about 35665.1583621887. The cubic root of 1272003521 is about 1083.5013027337.

The spelling of 1272003521 in words is "one billion, two hundred seventy-two million, three thousand, five hundred twenty-one".