21132807 has 16 divisors (see below), whose sum is σ = 29808000. Its totient is φ = 13280544.

The previous prime is 21132773. The next prime is 21132817. The reversal of 21132807 is 70823112.

It is not a de Polignac number, because 21132807 - 2¹⁶ = 21067271 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21132817) 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 15 ways as a sum of consecutive naturals, for example, 12244 + ... + 13862.

It is an arithmetic number, because the mean of its divisors is an integer number (1863000).

Almost surely, 2^21132807 is an apocalyptic number.

21132807 is a deficient number, since it is larger than the sum of its proper divisors (8675193).

21132807 is a wasteful number, since it uses less digits than its factorization.

21132807 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1870.

The product of its (nonzero) digits is 672, while the sum is 24.

The square root of 21132807 is about 4597.0432888978. The cubic root of 21132807 is about 276.4727902531.

Adding to 21132807 its reverse (70823112), we get a palindrome (91955919).

The spelling of 21132807 in words is "twenty-one million, one hundred thirty-two thousand, eight hundred seven".