20772571 has 4 divisors (see below), whose sum is σ = 20801872. Its totient is φ = 20743272.

The previous prime is 20772559. The next prime is 20772581. The reversal of 20772571 is 17527702.

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 20772571 - 2⁷ = 20772443 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20772581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13560 + ... + 15013.

It is an arithmetic number, because the mean of its divisors is an integer number (5200468).

Almost surely, 2^20772571 is an apocalyptic number.

20772571 is a deficient number, since it is larger than the sum of its proper divisors (29301).

20772571 is an equidigital number, since it uses as much as digits as its factorization.

20772571 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29300.

The product of its (nonzero) digits is 6860, while the sum is 31.

The square root of 20772571 is about 4557.6936053228. The cubic root of 20772571 is about 274.8928331739.

The spelling of 20772571 in words is "twenty million, seven hundred seventy-two thousand, five hundred seventy-one".