1253788138 has 4 divisors (see below), whose sum is σ = 1880682210. Its totient is φ = 626894068.

The previous prime is 1253788127. The next prime is 1253788163. The reversal of 1253788138 is 8318873521.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 878707449 + 375080689 = 29643^2 + 19367^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 313447033 + ... + 313447036.

Almost surely, 2^1253788138 is an apocalyptic number.

1253788138 is a deficient number, since it is larger than the sum of its proper divisors (626894072).

1253788138 is an equidigital number, since it uses as much as digits as its factorization.

1253788138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 626894071.

The product of its digits is 322560, while the sum is 46.

The square root of 1253788138 is about 35408.8708941700. The cubic root of 1253788138 is about 1078.3044204123.

The spelling of 1253788138 in words is "one billion, two hundred fifty-three million, seven hundred eighty-eight thousand, one hundred thirty-eight".