21634276 has 6 divisors (see below), whose sum is σ = 37859990. Its totient is φ = 10817136.

The previous prime is 21634271. The next prime is 21634279. The reversal of 21634276 is 67243612.

It can be written as a sum of positive squares in only one way, i.e., 11560000 + 10074276 = 3400^2 + 3174^2 .

It is not an unprimeable number, because it can be changed into a prime (21634271) 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 as a sum of consecutive naturals, namely, 2704281 + ... + 2704288.

Almost surely, 2^21634276 is an apocalyptic number.

It is an amenable number.

21634276 is a deficient number, since it is larger than the sum of its proper divisors (16225714).

21634276 is a wasteful number, since it uses less digits than its factorization.

21634276 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5408573 (or 5408571 counting only the distinct ones).

The product of its digits is 12096, while the sum is 31.

The square root of 21634276 is about 4651.2660642023. The cubic root of 21634276 is about 278.6425624422.

Adding to 21634276 its reverse (67243612), we get a palindrome (88877888).

The spelling of 21634276 in words is "twenty-one million, six hundred thirty-four thousand, two hundred seventy-six".