1251245140 has 12 divisors (see below), whose sum is σ = 2627614836. Its totient is φ = 500498048.

The previous prime is 1251245137. The next prime is 1251245143. The reversal of 1251245140 is 415421521.

It is an interprime number because it is at equal distance from previous prime (1251245137) and next prime (1251245143).

It can be written as a sum of positive squares in 2 ways, for example, as 142754704 + 1108490436 = 11948^2 + 33294^2 .

It is a super-2 number, since 2×1251245140² = 3131228800747239200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1251245143) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31281109 + ... + 31281148.

It is an arithmetic number, because the mean of its divisors is an integer number (218967903).

Almost surely, 2^1251245140 is an apocalyptic number.

1251245140 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1251245140 is an abundant number, since it is smaller than the sum of its proper divisors (1376369696).

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

1251245140 is a wasteful number, since it uses less digits than its factorization.

1251245140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62562266 (or 62562264 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 25.

The square root of 1251245140 is about 35372.9436151418. The cubic root of 1251245140 is about 1077.5749026944.

Adding to 1251245140 its reverse (415421521), we get a palindrome (1666666661).

The spelling of 1251245140 in words is "one billion, two hundred fifty-one million, two hundred forty-five thousand, one hundred forty".