1251251258 has 4 divisors (see below), whose sum is σ = 1876876890. Its totient is φ = 625625628.

The previous prime is 1251251227. The next prime is 1251251263. The reversal of 1251251258 is 8521521521.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 661878529 + 589372729 = 25727^2 + 24277^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 312812813 + ... + 312812816.

Almost surely, 2^1251251258 is an apocalyptic number.

1251251258 is a deficient number, since it is larger than the sum of its proper divisors (625625632).

1251251258 is an equidigital number, since it uses as much as digits as its factorization.

1251251258 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 625625631.

The product of its digits is 8000, while the sum is 32.

The square root of 1251251258 is about 35373.0300935614. The cubic root of 1251251258 is about 1077.5766589696.

Adding to 1251251258 its reverse (8521521521), we get a palindrome (9772772779).

The spelling of 1251251258 in words is "one billion, two hundred fifty-one million, two hundred fifty-one thousand, two hundred fifty-eight".