1251627138 has 12 divisors (see below), whose sum is σ = 2711858838. Its totient is φ = 417209040.

The previous prime is 1251627137. The next prime is 1251627151. The reversal of 1251627138 is 8317261521.

1251627138 is a `hidden beast` number, since 1 + 2 + 516 + 2 + 7 + 138 = 666.

It can be written as a sum of positive squares in only one way, i.e., 954995409 + 296631729 = 30903^2 + 17223^2 .

It is not an unprimeable number, because it can be changed into a prime (1251627137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 34767403 + ... + 34767438.

Almost surely, 2^1251627138 is an apocalyptic number.

1251627138 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

1251627138 is an abundant number, since it is smaller than the sum of its proper divisors (1460231700).

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

1251627138 is a wasteful number, since it uses less digits than its factorization.

1251627138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69534849 (or 69534846 counting only the distinct ones).

The product of its digits is 20160, while the sum is 36.

The square root of 1251627138 is about 35378.3427819902. The cubic root of 1251627138 is about 1077.6845506927.

Adding to 1251627138 its reverse (8317261521), we get a palindrome (9568888659).

The spelling of 1251627138 in words is "one billion, two hundred fifty-one million, six hundred twenty-seven thousand, one hundred thirty-eight".