1251040100 has 54 divisors (see below), whose sum is σ = 2737391202. Its totient is φ = 496272000.

The previous prime is 1251040099. The next prime is 1251040103. The reversal of 1251040100 is 10401521.

It can be written as a sum of positive squares in 3 ways, for example, as 139617856 + 1111422244 = 11816^2 + 33338^2 .

It is not an unprimeable number, because it can be changed into a prime (1251040103) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 4451960 + ... + 4452240.

Almost surely, 2^1251040100 is an apocalyptic number.

1251040100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1251040100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1368695601).

1251040100 is an abundant number, since it is smaller than the sum of its proper divisors (1486351102).

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

1251040100 is a wasteful number, since it uses less digits than its factorization.

1251040100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 717 (or 499 counting only the distinct ones).

The product of its (nonzero) digits is 40, while the sum is 14.

The square root of 1251040100 is about 35370.0452360468. The cubic root of 1251040100 is about 1077.5160391883.

Adding to 1251040100 its reverse (10401521), we get a palindrome (1261441621).

The spelling of 1251040100 in words is "one billion, two hundred fifty-one million, forty thousand, one hundred".