1270321721 has 2 divisors, whose sum is σ = 1270321722. Its totient is φ = 1270321720.

The previous prime is 1270321711. The next prime is 1270321727. The reversal of 1270321721 is 1271230721.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 694849600 + 575472121 = 26360^2 + 23989^2 .

It is a cyclic number.

It is not a de Polignac number, because 1270321721 - 2²² = 1266127417 is a prime.

It is a super-2 number, since 2×1270321721² = 3227434549688803682, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1270321727) 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 as a sum of consecutive naturals, namely, 635160860 + 635160861.

It is an arithmetic number, because the mean of its divisors is an integer number (635160861).

Almost surely, 2^1270321721 is an apocalyptic number.

It is an amenable number.

1270321721 is a deficient number, since it is larger than the sum of its proper divisors (1).

1270321721 is an equidigital number, since it uses as much as digits as its factorization.

1270321721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1176, while the sum is 26.

The square root of 1270321721 is about 35641.5729310590. The cubic root of 1270321721 is about 1083.0235692082.

The spelling of 1270321721 in words is "one billion, two hundred seventy million, three hundred twenty-one thousand, seven hundred twenty-one".