20275021 has 4 divisors (see below), whose sum is σ = 21834652. Its totient is φ = 18715392.

The previous prime is 20275019. The next prime is 20275049. The reversal of 20275021 is 12057202.

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

It can be written as a sum of positive squares in 2 ways, for example, as 1999396 + 18275625 = 1414^2 + 4275^2 .

It is a cyclic number.

It is not a de Polignac number, because 20275021 - 2¹ = 20275019 is a prime.

It is a super-2 number, since 2×20275021² = 822152953100882, which contains 22 as substring.

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 20275021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20275051) 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, 779796 + ... + 779821.

It is an arithmetic number, because the mean of its divisors is an integer number (5458663).

Almost surely, 2^20275021 is an apocalyptic number.

It is an amenable number.

20275021 is a deficient number, since it is larger than the sum of its proper divisors (1559631).

20275021 is a wasteful number, since it uses less digits than its factorization.

20275021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1559630.

The product of its (nonzero) digits is 280, while the sum is 19.

The square root of 20275021 is about 4502.7792528615. The cubic root of 20275021 is about 272.6803048782.

The spelling of 20275021 in words is "twenty million, two hundred seventy-five thousand, twenty-one".