21164133405 has 8 divisors (see below), whose sum is σ = 33862613472. Its totient is φ = 11287537808.

The previous prime is 21164133401. The next prime is 21164133409. The reversal of 21164133405 is 50433146112.

It is an interprime number because it is at equal distance from previous prime (21164133401) and next prime (21164133409).

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 21164133405 - 2² = 21164133401 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21164133401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 705471099 + ... + 705471128.

It is an arithmetic number, because the mean of its divisors is an integer number (4232826684).

Almost surely, 2^21164133405 is an apocalyptic number.

It is an amenable number.

21164133405 is a deficient number, since it is larger than the sum of its proper divisors (12698480067).

21164133405 is a wasteful number, since it uses less digits than its factorization.

21164133405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1410942235.

The product of its (nonzero) digits is 8640, while the sum is 30.

Adding to 21164133405 its reverse (50433146112), we get a palindrome (71597279517).

The spelling of 21164133405 in words is "twenty-one billion, one hundred sixty-four million, one hundred thirty-three thousand, four hundred five".