1384751721 has 4 divisors (see below), whose sum is σ = 1846335632. Its totient is φ = 923167812.

The previous prime is 1384751707. The next prime is 1384751729. The reversal of 1384751721 is 1271574831.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 1384751721 - 2⁶ = 1384751657 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1384751721.

It is not an unprimeable number, because it can be changed into a prime (1384751729) 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 3 ways as a sum of consecutive naturals, for example, 230791951 + ... + 230791956.

It is an arithmetic number, because the mean of its divisors is an integer number (461583908).

Almost surely, 2^1384751721 is an apocalyptic number.

It is an amenable number.

1384751721 is a deficient number, since it is larger than the sum of its proper divisors (461583911).

1384751721 is an equidigital number, since it uses as much as digits as its factorization.

1384751721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 461583910.

The product of its digits is 47040, while the sum is 39.

The square root of 1384751721 is about 37212.2522967906. The cubic root of 1384751721 is about 1114.6126590649.

The spelling of 1384751721 in words is "one billion, three hundred eighty-four million, seven hundred fifty-one thousand, seven hundred twenty-one".