1273601921 has 2 divisors, whose sum is σ = 1273601922. Its totient is φ = 1273601920.

The previous prime is 1273601909. The next prime is 1273601929. The reversal of 1273601921 is 1291063721.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 802928896 + 470673025 = 28336^2 + 21695^2 .

It is an emirp because it is prime and its reverse (1291063721) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1273601921 - 2²² = 1269407617 is a prime.

It is not a weakly prime, because it can be changed into another prime (1273601929) 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, 636800960 + 636800961.

It is an arithmetic number, because the mean of its divisors is an integer number (636800961).

Almost surely, 2^1273601921 is an apocalyptic number.

It is an amenable number.

1273601921 is a deficient number, since it is larger than the sum of its proper divisors (1).

1273601921 is an equidigital number, since it uses as much as digits as its factorization.

1273601921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4536, while the sum is 32.

The square root of 1273601921 is about 35687.5597512635. The cubic root of 1273601921 is about 1083.9549554523.

The spelling of 1273601921 in words is "one billion, two hundred seventy-three million, six hundred one thousand, nine hundred twenty-one".