21001132 has 24 divisors (see below), whose sum is σ = 37442160. Its totient is φ = 10305600.

The previous prime is 21001121. The next prime is 21001153. The reversal of 21001132 is 23110012.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 91594 + ... + 91822.

It is an arithmetic number, because the mean of its divisors is an integer number (1560090).

Almost surely, 2^21001132 is an apocalyptic number.

It is an amenable number.

21001132 is a deficient number, since it is larger than the sum of its proper divisors (16441028).

21001132 is a wasteful number, since it uses less digits than its factorization.

21001132 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 561 (or 559 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 10.

The square root of 21001132 is about 4582.6992046173. The cubic root of 21001132 is about 275.8973748541.

Adding to 21001132 its reverse (23110012), we get a palindrome (44111144).

The spelling of 21001132 in words is "twenty-one million, one thousand, one hundred thirty-two".