21235912 has 8 divisors (see below), whose sum is σ = 39817350. Its totient is φ = 10617952.

The previous prime is 21235883. The next prime is 21235931. The reversal of 21235912 is 21953212.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 18783556 + 2452356 = 4334^2 + 1566^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1327237 + ... + 1327252.

Almost surely, 2^21235912 is an apocalyptic number.

It is an amenable number.

21235912 is a deficient number, since it is larger than the sum of its proper divisors (18581438).

21235912 is a wasteful number, since it uses less digits than its factorization.

21235912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2654495 (or 2654491 counting only the distinct ones).

The product of its digits is 1080, while the sum is 25.

The square root of 21235912 is about 4608.2439171554. The cubic root of 21235912 is about 276.9216893409.

The spelling of 21235912 in words is "twenty-one million, two hundred thirty-five thousand, nine hundred twelve".