21326129 has 24 divisors (see below), whose sum is σ = 25025280. Its totient is φ = 18120960.

The previous prime is 21326119. The next prime is 21326131. The reversal of 21326129 is 92162312.

It is a de Polignac number, because none of the positive numbers 2^k-21326129 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21326098 and 21326107.

It is not an unprimeable number, because it can be changed into a prime (21326119) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 219809 + ... + 219905.

It is an arithmetic number, because the mean of its divisors is an integer number (1042720).

Almost surely, 2^21326129 is an apocalyptic number.

It is an amenable number.

21326129 is a deficient number, since it is larger than the sum of its proper divisors (3699151).

21326129 is a wasteful number, since it uses less digits than its factorization.

21326129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221 (or 210 counting only the distinct ones).

The product of its digits is 1296, while the sum is 26.

The square root of 21326129 is about 4618.0221957024. The cubic root of 21326129 is about 277.3132861893.

The spelling of 21326129 in words is "twenty-one million, three hundred twenty-six thousand, one hundred twenty-nine".