21385928211 has 8 divisors (see below), whose sum is σ = 30015337920. Its totient is φ = 13506901992.

The previous prime is 21385928191. The next prime is 21385928231. The reversal of 21385928211 is 11282958312.

It is an interprime number because it is at equal distance from previous prime (21385928191) and next prime (21385928231).

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

It is not a de Polignac number, because 21385928211 - 2⁶ = 21385928147 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21385928231) 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, 187595805 + ... + 187595918.

It is an arithmetic number, because the mean of its divisors is an integer number (3751917240).

Almost surely, 2^21385928211 is an apocalyptic number.

21385928211 is a deficient number, since it is larger than the sum of its proper divisors (8629409709).

21385928211 is a wasteful number, since it uses less digits than its factorization.

21385928211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 375191745.

The product of its digits is 69120, while the sum is 42.

The spelling of 21385928211 in words is "twenty-one billion, three hundred eighty-five million, nine hundred twenty-eight thousand, two hundred eleven".