938340515921 has 4 divisors (see below), whose sum is σ = 938343168000. Its totient is φ = 938337863844.

The previous prime is 938340515863. The next prime is 938340515939. The reversal of 938340515921 is 129515043839.

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, and also an emirpimes, since its reverse is a distinct semiprime: 129515043839 = 73597 ⋅1759787.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-938340515921 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 938340515921.

It is not an unprimeable number, because it can be changed into a prime (938340515941) 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 3 ways as a sum of consecutive naturals, for example, 695321 + ... + 1536278.

It is an arithmetic number, because the mean of its divisors is an integer number (234585792000).

Almost surely, 2^938340515921 is an apocalyptic number.

It is an amenable number.

938340515921 is a deficient number, since it is larger than the sum of its proper divisors (2652079).

938340515921 is a wasteful number, since it uses less digits than its factorization.

938340515921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2652078.

The product of its (nonzero) digits is 1166400, while the sum is 50.

The spelling of 938340515921 in words is "nine hundred thirty-eight billion, three hundred forty million, five hundred fifteen thousand, nine hundred twenty-one".