21277252 has 6 divisors (see below), whose sum is σ = 37235198. Its totient is φ = 10638624.

The previous prime is 21277247. The next prime is 21277261. The reversal of 21277252 is 25277212.

21277252 is nontrivially palindromic in base 7.

It can be written as a sum of positive squares in only one way, i.e., 21013056 + 264196 = 4584^2 + 514^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21277252.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2659653 + ... + 2659660.

Almost surely, 2^21277252 is an apocalyptic number.

It is an amenable number.

21277252 is a deficient number, since it is larger than the sum of its proper divisors (15957946).

21277252 is a wasteful number, since it uses less digits than its factorization.

21277252 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5319317 (or 5319315 counting only the distinct ones).

The product of its digits is 3920, while the sum is 28.

The square root of 21277252 is about 4612.7271759774. The cubic root of 21277252 is about 277.1012675649.

The spelling of 21277252 in words is "twenty-one million, two hundred seventy-seven thousand, two hundred fifty-two".