21000164361 has 16 divisors (see below), whose sum is σ = 30654410688. Its totient is φ = 12682073600.

The previous prime is 21000164323. The next prime is 21000164387. The reversal of 21000164361 is 16346100012.

It is a cyclic number.

It is not a de Polignac number, because 21000164361 - 2¹⁷ = 21000033289 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21000164321) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1123056 + ... + 1141601.

It is an arithmetic number, because the mean of its divisors is an integer number (1915900668).

Almost surely, 2^21000164361 is an apocalyptic number.

It is an amenable number.

21000164361 is a deficient number, since it is larger than the sum of its proper divisors (9654246327).

21000164361 is a wasteful number, since it uses less digits than its factorization.

21000164361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2264952.

The product of its (nonzero) digits is 864, while the sum is 24.

Adding to 21000164361 its reverse (16346100012), we get a palindrome (37346264373).

The spelling of 21000164361 in words is "twenty-one billion, one hundred sixty-four thousand, three hundred sixty-one".