20912447 has 8 divisors (see below), whose sum is σ = 21425712. Its totient is φ = 20404800.

The previous prime is 20912417. The next prime is 20912453. The reversal of 20912447 is 74421902.

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 20912447 - 2⁸ = 20912191 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 (20912417) 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, 6683 + ... + 9299.

It is an arithmetic number, because the mean of its divisors is an integer number (2678214).

Almost surely, 2^20912447 is an apocalyptic number.

20912447 is a deficient number, since it is larger than the sum of its proper divisors (513265).

20912447 is a wasteful number, since it uses less digits than its factorization.

20912447 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2809.

The product of its (nonzero) digits is 4032, while the sum is 29.

The square root of 20912447 is about 4573.0129017968. The cubic root of 20912447 is about 275.5084675423.

The spelling of 20912447 in words is "twenty million, nine hundred twelve thousand, four hundred forty-seven".