1250001281 has 2 divisors, whose sum is σ = 1250001282. Its totient is φ = 1250001280.

The previous prime is 1250001227. The next prime is 1250001299. The reversal of 1250001281 is 1821000521.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 833188225 + 416813056 = 28865^2 + 20416^2 .

It is an emirp because it is prime and its reverse (1821000521) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1250001281 is a prime.

It is a super-2 number, since 2×1250001281² = 3125006405003281922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1250000281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 625000640 + 625000641.

It is an arithmetic number, because the mean of its divisors is an integer number (625000641).

Almost surely, 2^1250001281 is an apocalyptic number.

It is an amenable number.

1250001281 is a deficient number, since it is larger than the sum of its proper divisors (1).

1250001281 is an equidigital number, since it uses as much as digits as its factorization.

1250001281 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 160, while the sum is 20.

The square root of 1250001281 is about 35355.3571753985. The cubic root of 1250001281 is about 1077.2177129933.

The spelling of 1250001281 in words is "one billion, two hundred fifty million, one thousand, two hundred eighty-one".