21227554 has 4 divisors (see below), whose sum is σ = 31841334. Its totient is φ = 10613776.

The previous prime is 21227533. The next prime is 21227561. The reversal of 21227554 is 45572212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 17514225 + 3713329 = 4185^2 + 1927^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5306887 + ... + 5306890.

Almost surely, 2^21227554 is an apocalyptic number.

21227554 is a deficient number, since it is larger than the sum of its proper divisors (10613780).

21227554 is a wasteful number, since it uses less digits than its factorization.

21227554 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10613779.

The product of its digits is 5600, while the sum is 28.

The square root of 21227554 is about 4607.3369748695. The cubic root of 21227554 is about 276.8853544256.

Adding to 21227554 its reverse (45572212), we get a palindrome (66799766).

The spelling of 21227554 in words is "twenty-one million, two hundred twenty-seven thousand, five hundred fifty-four".