1388647121 has 8 divisors (see below), whose sum is σ = 1396569600. Its totient is φ = 1380742720.

The previous prime is 1388647097. The next prime is 1388647151. The reversal of 1388647121 is 1217468831.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1388647121 is a prime.

It is a super-3 number, since 3×1388647121³ (a number of 28 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1388647151) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 167801 + ... + 175881.

It is an arithmetic number, because the mean of its divisors is an integer number (174571200).

Almost surely, 2^1388647121 is an apocalyptic number.

It is an amenable number.

1388647121 is a deficient number, since it is larger than the sum of its proper divisors (7922479).

1388647121 is an equidigital number, since it uses as much as digits as its factorization.

1388647121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9039.

The product of its digits is 64512, while the sum is 41.

The square root of 1388647121 is about 37264.5558272201. Note that the first 3 decimals coincide. The cubic root of 1388647121 is about 1115.6568407570.

The spelling of 1388647121 in words is "one billion, three hundred eighty-eight million, six hundred forty-seven thousand, one hundred twenty-one".