21199432 has 8 divisors (see below), whose sum is σ = 39748950. Its totient is φ = 10599712.

The previous prime is 21199427. The next prime is 21199441. The reversal of 21199432 is 23499112.

It can be written as a sum of positive squares in only one way, i.e., 16208676 + 4990756 = 4026^2 + 2234^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a junction number, because it is equal to n+sod(n) for n = 21199394 and 21199403.

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 as a sum of consecutive naturals, namely, 1324957 + ... + 1324972.

Almost surely, 2^21199432 is an apocalyptic number.

It is an amenable number.

21199432 is a deficient number, since it is larger than the sum of its proper divisors (18549518).

21199432 is a wasteful number, since it uses less digits than its factorization.

21199432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2649935 (or 2649931 counting only the distinct ones).

The product of its digits is 3888, while the sum is 31.

The square root of 21199432 is about 4604.2840920169. The cubic root of 21199432 is about 276.7630289646.

The spelling of 21199432 in words is "twenty-one million, one hundred ninety-nine thousand, four hundred thirty-two".