20447287 has 8 divisors (see below), whose sum is σ = 24598400. Its totient is φ = 16603704.

The previous prime is 20447281. The next prime is 20447293. The reversal of 20447287 is 78274402.

It is an interprime number because it is at equal distance from previous prime (20447281) and next prime (20447293).

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 20447287 - 2³ = 20447279 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 (20447281) 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, 76737 + ... + 77002.

It is an arithmetic number, because the mean of its divisors is an integer number (3074800).

Almost surely, 2^20447287 is an apocalyptic number.

20447287 is a deficient number, since it is larger than the sum of its proper divisors (4151113).

20447287 is a wasteful number, since it uses less digits than its factorization.

20447287 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153765.

The product of its (nonzero) digits is 25088, while the sum is 34.

The square root of 20447287 is about 4521.8676451219. The cubic root of 20447287 is about 273.4504008085.

The spelling of 20447287 in words is "twenty million, four hundred forty-seven thousand, two hundred eighty-seven".