21887522 has 8 divisors (see below), whose sum is σ = 33632172. Its totient is φ = 10676800.

The previous prime is 21887507. The next prime is 21887533. The reversal of 21887522 is 22578812.

It can be written as a sum of positive squares in 2 ways, for example, as 14753281 + 7134241 = 3841^2 + 2671^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 133379 + ... + 133542.

Almost surely, 2^21887522 is an apocalyptic number.

21887522 is a deficient number, since it is larger than the sum of its proper divisors (11744650).

21887522 is a wasteful number, since it uses less digits than its factorization.

21887522 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 266964.

The product of its digits is 17920, while the sum is 35.

The square root of 21887522 is about 4678.4102000573. The cubic root of 21887522 is about 279.7255899998.

The spelling of 21887522 in words is "twenty-one million, eight hundred eighty-seven thousand, five hundred twenty-two".