21164389277 has 8 divisors (see below), whose sum is σ = 21869758176. Its totient is φ = 20466039312.

The previous prime is 21164389229. The next prime is 21164389291. The reversal of 21164389277 is 77298346112.

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 21164389277 - 2¹² = 21164385181 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 (21164389217) 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, 1748603 + ... + 1760664.

It is an arithmetic number, because the mean of its divisors is an integer number (2733719772).

Almost surely, 2^21164389277 is an apocalyptic number.

It is an amenable number.

21164389277 is a deficient number, since it is larger than the sum of its proper divisors (705368899).

21164389277 is a wasteful number, since it uses less digits than its factorization.

21164389277 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3509467.

The product of its digits is 1016064, while the sum is 50.

The spelling of 21164389277 in words is "twenty-one billion, one hundred sixty-four million, three hundred eighty-nine thousand, two hundred seventy-seven".