21214454 has 4 divisors (see below), whose sum is σ = 31821684.
Its totient is φ = 10607226.
The previous prime is 21214451. The next prime is 21214463. The reversal of 21214454 is 45441212.
It is a semiprime because it is the product of two primes.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (21214451) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5303612 + ... + 5303615.
It is an arithmetic number, because the mean of its divisors is an integer number (7955421).
Almost surely, 221214454 is an apocalyptic number.
21214454 is a deficient number, since it is larger than the sum of its proper divisors (10607230).
21214454 is a wasteful number, since it uses less digits than its factorization.
21214454 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 10607229.
The product of its digits is 1280, while the sum is 23.
The square root of 21214454 is about 4605.9151099429.
The cubic root of 21214454 is about 276.8283853162.
Adding to 21214454 its reverse (45441212), we get a palindrome (66655666).
The spelling of 21214454 in words is "twenty-one million, two hundred fourteen thousand, four hundred fifty-four".