21271436 has 6 divisors (see below), whose sum is σ = 37225020. Its totient is φ = 10635716.

The previous prime is 21271429. The next prime is 21271451. The reversal of 21271436 is 63417212.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2658926 + ... + 2658933.

It is an arithmetic number, because the mean of its divisors is an integer number (6204170).

Almost surely, 2^21271436 is an apocalyptic number.

It is an amenable number.

21271436 is a deficient number, since it is larger than the sum of its proper divisors (15953584).

21271436 is a wasteful number, since it uses less digits than its factorization.

21271436 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5317863 (or 5317861 counting only the distinct ones).

The product of its digits is 2016, while the sum is 26.

The square root of 21271436 is about 4612.0967032360. The cubic root of 21271436 is about 277.0760173143.

Adding to 21271436 its reverse (63417212), we get a palindrome (84688648).

The spelling of 21271436 in words is "twenty-one million, two hundred seventy-one thousand, four hundred thirty-six".