1388641250 has 20 divisors (see below), whose sum is σ = 2602871502. Its totient is φ = 555456000.

The previous prime is 1388641229. The next prime is 1388641253. The reversal of 1388641250 is 521468831.

It can be written as a sum of positive squares in 5 ways, for example, as 12453841 + 1376187409 = 3529^2 + 37097^2 .

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (1388641253) by changing a digit.

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 in 9 ways as a sum of consecutive naturals, for example, 554207 + ... + 556706.

Almost surely, 2^1388641250 is an apocalyptic number.

1388641250 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1388641250 is a deficient number, since it is larger than the sum of its proper divisors (1214230252).

1388641250 is an equidigital number, since it uses as much as digits as its factorization.

1388641250 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1110935 (or 1110920 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 38.

The square root of 1388641250 is about 37264.4770525497. The cubic root of 1388641250 is about 1115.6552684760.

The spelling of 1388641250 in words is "one billion, three hundred eighty-eight million, six hundred forty-one thousand, two hundred fifty".