1251250081 has 2 divisors, whose sum is σ = 1251250082. Its totient is φ = 1251250080.

The previous prime is 1251250043. The next prime is 1251250087. The reversal of 1251250081 is 1800521521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 716900625 + 534349456 = 26775^2 + 23116^2 .

It is a cyclic number.

It is not a de Polignac number, because 1251250081 - 2¹³ = 1251241889 is a prime.

It is a super-2 number, since 2×1251250081² = 3131253530405013122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1251250087) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 625625040 + 625625041.

It is an arithmetic number, because the mean of its divisors is an integer number (625625041).

Almost surely, 2^1251250081 is an apocalyptic number.

It is an amenable number.

1251250081 is a deficient number, since it is larger than the sum of its proper divisors (1).

1251250081 is an equidigital number, since it uses as much as digits as its factorization.

1251250081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 800, while the sum is 25.

The square root of 1251250081 is about 35373.0134565886. The cubic root of 1251250081 is about 1077.5763210923.

The spelling of 1251250081 in words is "one billion, two hundred fifty-one million, two hundred fifty thousand, eighty-one".