1251141440 has 28 divisors (see below), whose sum is σ = 2979281316. Its totient is φ = 500456448.

The previous prime is 1251141427. The next prime is 1251141449. The reversal of 1251141440 is 441411521.

It can be written as a sum of positive squares in 2 ways, for example, as 433638976 + 817502464 = 20824^2 + 28592^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1251141449) by changing a digit.

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 in 3 ways as a sum of consecutive naturals, for example, 1954589 + ... + 1955228.

Almost surely, 2^1251141440 is an apocalyptic number.

1251141440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1251141440 is an abundant number, since it is smaller than the sum of its proper divisors (1728139876).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1251141440 is an equidigital number, since it uses as much as digits as its factorization.

1251141440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3909834 (or 3909824 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 23.

The square root of 1251141440 is about 35371.4777751793. The cubic root of 1251141440 is about 1077.5451329871.

Adding to 1251141440 its reverse (441411521), we get a palindrome (1692552961).

The spelling of 1251141440 in words is "one billion, two hundred fifty-one million, one hundred forty-one thousand, four hundred forty".