1251405200 has 60 divisors (see below), whose sum is σ = 3011685588. Its totient is φ = 499699200.

The previous prime is 1251405167. The next prime is 1251405209. The reversal of 1251405200 is 25041521.

It can be written as a sum of positive squares in 6 ways, for example, as 31719424 + 1219685776 = 5632^2 + 34924^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (1251405209) 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, 262034 + ... + 266766.

Almost surely, 2^1251405200 is an apocalyptic number.

1251405200 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 1251405200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1505842794).

1251405200 is an abundant number, since it is smaller than the sum of its proper divisors (1760280388).

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

1251405200 is a wasteful number, since it uses less digits than its factorization.

1251405200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5412 (or 5401 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 20.

The square root of 1251405200 is about 35375.2060064673. The cubic root of 1251405200 is about 1077.6208487363.

Adding to 1251405200 its reverse (25041521), we get a palindrome (1276446721).

The spelling of 1251405200 in words is "one billion, two hundred fifty-one million, four hundred five thousand, two hundred".