21413447 has 8 divisors (see below), whose sum is σ = 23401872. Its totient is φ = 19432000.

The previous prime is 21413443. The next prime is 21413449. The reversal of 21413447 is 74431412.

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 21413447 - 2² = 21413443 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21413443) 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, 6323 + ... + 9099.

It is an arithmetic number, because the mean of its divisors is an integer number (2925234).

Almost surely, 2^21413447 is an apocalyptic number.

21413447 is a deficient number, since it is larger than the sum of its proper divisors (1988425).

21413447 is a wasteful number, since it uses less digits than its factorization.

21413447 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3489.

The product of its digits is 2688, while the sum is 26.

The square root of 21413447 is about 4627.4665855087. The cubic root of 21413447 is about 277.6912492741.

Adding to 21413447 its reverse (74431412), we get a palindrome (95844859).

The spelling of 21413447 in words is "twenty-one million, four hundred thirteen thousand, four hundred forty-seven".