20576891 has 4 divisors (see below), whose sum is σ = 20708112. Its totient is φ = 20445672.

The previous prime is 20576887. The next prime is 20576903. The reversal of 20576891 is 19867502.

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 20576891 - 2² = 20576887 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20576861) 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, 65375 + ... + 65688.

It is an arithmetic number, because the mean of its divisors is an integer number (5177028).

Almost surely, 2^20576891 is an apocalyptic number.

20576891 is a deficient number, since it is larger than the sum of its proper divisors (131221).

20576891 is a wasteful number, since it uses less digits than its factorization.

20576891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131220.

The product of its (nonzero) digits is 30240, while the sum is 38.

The square root of 20576891 is about 4536.1758122895. The cubic root of 20576891 is about 274.0269345004.

The spelling of 20576891 in words is "twenty million, five hundred seventy-six thousand, eight hundred ninety-one".