1251120040 has 16 divisors (see below), whose sum is σ = 2815020180. Its totient is φ = 500448000.

The previous prime is 1251120023. The next prime is 1251120107. The reversal of 1251120040 is 400211521.

It can be written as a sum of positive squares in 2 ways, for example, as 1008570564 + 242549476 = 31758^2 + 15574^2 .

It is a junction number, because it is equal to n+sod(n) for n = 1251119996 and 1251120023.

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 in 3 ways as a sum of consecutive naturals, for example, 15638961 + ... + 15639040.

Almost surely, 2^1251120040 is an apocalyptic number.

1251120040 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1251120040 is an abundant number, since it is smaller than the sum of its proper divisors (1563900140).

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

1251120040 is a wasteful number, since it uses less digits than its factorization.

1251120040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31278012 (or 31278008 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 16.

The square root of 1251120040 is about 35371.1752702677. The cubic root of 1251120040 is about 1077.5389893712.

Adding to 1251120040 its reverse (400211521), we get a palindrome (1651331561).

The spelling of 1251120040 in words is "one billion, two hundred fifty-one million, one hundred twenty thousand, forty".