21146400321 has 16 divisors (see below), whose sum is σ = 29117245248. Its totient is φ = 13640788800.

The previous prime is 21146400311. The next prime is 21146400323. The reversal of 21146400321 is 12300464112.

It is not a de Polignac number, because 21146400321 - 2¹³ = 21146392129 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21146400291 and 21146400300.

It is not an unprimeable number, because it can be changed into a prime (21146400323) 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 15 ways as a sum of consecutive naturals, for example, 506175 + ... + 546356.

It is an arithmetic number, because the mean of its divisors is an integer number (1819827828).

Almost surely, 2^21146400321 is an apocalyptic number.

It is an amenable number.

21146400321 is a deficient number, since it is larger than the sum of its proper divisors (7970844927).

21146400321 is a wasteful number, since it uses less digits than its factorization.

21146400321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1052752.

The product of its (nonzero) digits is 1152, while the sum is 24.

Adding to 21146400321 its reverse (12300464112), we get a palindrome (33446864433).

The spelling of 21146400321 in words is "twenty-one billion, one hundred forty-six million, four hundred thousand, three hundred twenty-one".