1389004721 has 8 divisors (see below), whose sum is σ = 1496713344. Its totient is φ = 1281419280.

The previous prime is 1389004697. The next prime is 1389004733. The reversal of 1389004721 is 1274009831.

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

It is a cyclic number.

It is not a de Polignac number, because 1389004721 - 2⁶ = 1389004657 is a prime.

It is a super-2 number, since 2×1389004721² = 3858668229920575682, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1389004121) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6665 + ... + 53126.

It is an arithmetic number, because the mean of its divisors is an integer number (187089168).

Almost surely, 2^1389004721 is an apocalyptic number.

It is an amenable number.

1389004721 is a deficient number, since it is larger than the sum of its proper divisors (107708623).

1389004721 is a wasteful number, since it uses less digits than its factorization.

1389004721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61591.

The product of its (nonzero) digits is 12096, while the sum is 35.

The square root of 1389004721 is about 37269.3536434428. The cubic root of 1389004721 is about 1115.7525993408.

The spelling of 1389004721 in words is "one billion, three hundred eighty-nine million, four thousand, seven hundred twenty-one".