20523623 has 2 divisors, whose sum is σ = 20523624. Its totient is φ = 20523622.

The previous prime is 20523611. The next prime is 20523649. The reversal of 20523623 is 32632502.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20523623 is a prime.

It is a super-2 number, since 2×20523623² = 842438202092258, which contains 22 as substring.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20523653) 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 as a sum of consecutive naturals, namely, 10261811 + 10261812.

It is an arithmetic number, because the mean of its divisors is an integer number (10261812).

Almost surely, 2^20523623 is an apocalyptic number.

20523623 is a deficient number, since it is larger than the sum of its proper divisors (1).

20523623 is an equidigital number, since it uses as much as digits as its factorization.

20523623 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2160, while the sum is 23.

The square root of 20523623 is about 4530.3005419067. The cubic root of 20523623 is about 273.7902696470.

The spelling of 20523623 in words is "twenty million, five hundred twenty-three thousand, six hundred twenty-three".