20730847 has 4 divisors (see below), whose sum is σ = 21399616. Its totient is φ = 20062080.

The previous prime is 20730839. The next prime is 20730869. The reversal of 20730847 is 74803702.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20730847 - 2³ = 20730839 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (31), and also a Moran number because the ratio is a prime number: 668737 = 20730847 / (2 + 0 + 7 + 3 + 0 + 8 + 4 + 7).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20730887) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 334338 + ... + 334399.

It is an arithmetic number, because the mean of its divisors is an integer number (5349904).

Almost surely, 2^20730847 is an apocalyptic number.

20730847 is a deficient number, since it is larger than the sum of its proper divisors (668769).

20730847 is an equidigital number, since it uses as much as digits as its factorization.

20730847 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 668768.

The product of its (nonzero) digits is 9408, while the sum is 31.

The square root of 20730847 is about 4553.1139893484. The cubic root of 20730847 is about 274.7086589490.

The spelling of 20730847 in words is "twenty million, seven hundred thirty thousand, eight hundred forty-seven".