20523687 has 4 divisors (see below), whose sum is σ = 27364920. Its totient is φ = 13682456.

The previous prime is 20523673. The next prime is 20523691. The reversal of 20523687 is 78632502.

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 20523687 - 2⁶ = 20523623 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20523697) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3420612 + ... + 3420617.

It is an arithmetic number, because the mean of its divisors is an integer number (6841230).

Almost surely, 2^20523687 is an apocalyptic number.

20523687 is a deficient number, since it is larger than the sum of its proper divisors (6841233).

20523687 is an equidigital number, since it uses as much as digits as its factorization.

20523687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6841232.

The product of its (nonzero) digits is 20160, while the sum is 33.

The square root of 20523687 is about 4530.3076054502. The cubic root of 20523687 is about 273.7905542387.

The spelling of 20523687 in words is "twenty million, five hundred twenty-three thousand, six hundred eighty-seven".