1389788987821 has 8 divisors (see below), whose sum is σ = 1497010927104. Its totient is φ = 1282612062000.

The previous prime is 1389788987819. The next prime is 1389788987893. The reversal of 1389788987821 is 1287898879831.

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 1389788987821 - 2¹ = 1389788987819 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1389788981821) 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, 11189221 + ... + 11312746.

It is an arithmetic number, because the mean of its divisors is an integer number (187126365888).

Almost surely, 2^{1389788987821} is an apocalyptic number.

It is an amenable number.

1389788987821 is a deficient number, since it is larger than the sum of its proper divisors (107221939283).

1389788987821 is a wasteful number, since it uses less digits than its factorization.

1389788987821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22506731.

The product of its digits is 780337152, while the sum is 79.

The spelling of 1389788987821 in words is "one trillion, three hundred eighty-nine billion, seven hundred eighty-eight million, nine hundred eighty-seven thousand, eight hundred twenty-one".