21522206 has 8 divisors (see below), whose sum is σ = 32569344. Its totient is φ = 10665760.

The previous prime is 21522173. The next prime is 21522217. The reversal of 21522206 is 60222512.

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

It is a super-2 number, since 2×21522206² = 926410702212872, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 47390 + ... + 47841.

It is an arithmetic number, because the mean of its divisors is an integer number (4071168).

Almost surely, 2^21522206 is an apocalyptic number.

21522206 is a deficient number, since it is larger than the sum of its proper divisors (11047138).

21522206 is a wasteful number, since it uses less digits than its factorization.

21522206 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95346.

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 21522206 is about 4639.2031643376. The cubic root of 21522206 is about 278.1605873076.

Adding to 21522206 its reverse (60222512), we get a palindrome (81744718).

The spelling of 21522206 in words is "twenty-one million, five hundred twenty-two thousand, two hundred six".