1251521451 has 12 divisors (see below), whose sum is σ = 1826391112. Its totient is φ = 825745536.

The previous prime is 1251521399. The next prime is 1251521483. The reversal of 1251521451 is 1541251521.

It is a happy number.

1251521451 is a `hidden beast` number, since 1 + 2 + 515 + 2 + 145 + 1 = 666.

It is not a de Polignac number, because 1251521451 - 2⁶ = 1251521387 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1251521251) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 715921 + ... + 717666.

Almost surely, 2^1251521451 is an apocalyptic number.

1251521451 is a deficient number, since it is larger than the sum of its proper divisors (574869661).

1251521451 is a wasteful number, since it uses less digits than its factorization.

1251521451 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1433690 (or 1433687 counting only the distinct ones).

The product of its digits is 2000, while the sum is 27.

The square root of 1251521451 is about 35376.8490824155. The cubic root of 1251521451 is about 1077.6542167246.

Adding to 1251521451 its reverse (1541251521), we get a palindrome (2792772972).

The spelling of 1251521451 in words is "one billion, two hundred fifty-one million, five hundred twenty-one thousand, four hundred fifty-one".