21214147 has 8 divisors (see below), whose sum is σ = 22550400. Its totient is φ = 19887744.

The previous prime is 21214139. The next prime is 21214159. The reversal of 21214147 is 74141212.

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

It is a cyclic number.

It is not a de Polignac number, because 21214147 - 2³ = 21214139 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21214117) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 2254 + ... + 6892.

It is an arithmetic number, because the mean of its divisors is an integer number (2818800).

Almost surely, 2^21214147 is an apocalyptic number.

21214147 is a deficient number, since it is larger than the sum of its proper divisors (1336253).

21214147 is a wasteful number, since it uses less digits than its factorization.

21214147 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4925.

The product of its digits is 448, while the sum is 22.

The square root of 21214147 is about 4605.8817831117. The cubic root of 21214147 is about 276.8270499574.

Adding to 21214147 its reverse (74141212), we get a palindrome (95355359).

The spelling of 21214147 in words is "twenty-one million, two hundred fourteen thousand, one hundred forty-seven".