21214455 has 8 divisors (see below), whose sum is σ = 33943152. Its totient is φ = 11314368.

The previous prime is 21214451. The next prime is 21214463. The reversal of 21214455 is 55441212.

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

It is not a de Polignac number, because 21214455 - 2² = 21214451 is a prime.

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 in 7 ways as a sum of consecutive naturals, for example, 707134 + ... + 707163.

It is an arithmetic number, because the mean of its divisors is an integer number (4242894).

Almost surely, 2^21214455 is an apocalyptic number.

21214455 is a deficient number, since it is larger than the sum of its proper divisors (12728697).

21214455 is a wasteful number, since it uses less digits than its factorization.

21214455 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1414305.

The product of its digits is 1600, while the sum is 24.

The square root of 21214455 is about 4605.9152184989. The cubic root of 21214455 is about 276.8283896659.

Adding to 21214455 its reverse (55441212), we get a palindrome (76655667).

The spelling of 21214455 in words is "twenty-one million, two hundred fourteen thousand, four hundred fifty-five".