20428271 has 8 divisors (see below), whose sum is σ = 21797424. Its totient is φ = 19077760.

The previous prime is 20428241. The next prime is 20428273. The reversal of 20428271 is 17282402.

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 20428271 - 2¹⁰ = 20427247 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20428271.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20428273) 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, 2360 + ... + 6813.

It is an arithmetic number, because the mean of its divisors is an integer number (2724678).

Almost surely, 2^20428271 is an apocalyptic number.

20428271 is a deficient number, since it is larger than the sum of its proper divisors (1369153).

20428271 is a wasteful number, since it uses less digits than its factorization.

20428271 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9321.

The product of its (nonzero) digits is 1792, while the sum is 26.

The square root of 20428271 is about 4519.7644850147. The cubic root of 20428271 is about 273.3656047891.

The spelling of 20428271 in words is "twenty million, four hundred twenty-eight thousand, two hundred seventy-one".