1251516001 has 2 divisors, whose sum is σ = 1251516002. Its totient is φ = 1251516000.

The previous prime is 1251515983. The next prime is 1251516011. The reversal of 1251516001 is 1006151521.

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., 778410000 + 473106001 = 27900^2 + 21751^2 .

It is a cyclic number.

It is not a de Polignac number, because 1251516001 - 2¹¹ = 1251513953 is a prime.

It is not a weakly prime, because it can be changed into another prime (1251516011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 625758000 + 625758001.

It is an arithmetic number, because the mean of its divisors is an integer number (625758001).

Almost surely, 2^1251516001 is an apocalyptic number.

It is an amenable number.

1251516001 is a deficient number, since it is larger than the sum of its proper divisors (1).

1251516001 is an equidigital number, since it uses as much as digits as its factorization.

1251516001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 300, while the sum is 22.

The square root of 1251516001 is about 35376.7720545558. The cubic root of 1251516001 is about 1077.6526524355.

Adding to 1251516001 its reverse (1006151521), we get a palindrome (2257667522).

The spelling of 1251516001 in words is "one billion, two hundred fifty-one million, five hundred sixteen thousand, one".