20013523 has 2 divisors, whose sum is σ = 20013524. Its totient is φ = 20013522.

The previous prime is 20013491. The next prime is 20013529. The reversal of 20013523 is 32531002.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20013523 - 2⁵ = 20013491 is a prime.

It is a super-2 number, since 2×20013523² = 801082205743058, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20013497 and 20013506.

It is not a weakly prime, because it can be changed into another prime (20013529) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10006761 + 10006762.

It is an arithmetic number, because the mean of its divisors is an integer number (10006762).

Almost surely, 2^20013523 is an apocalyptic number.

20013523 is a deficient number, since it is larger than the sum of its proper divisors (1).

20013523 is an equidigital number, since it uses as much as digits as its factorization.

20013523 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 180, while the sum is 16.

The square root of 20013523 is about 4473.6476168782. The cubic root of 20013523 is about 271.5029263251.

Adding to 20013523 its reverse (32531002), we get a palindrome (52544525).

The spelling of 20013523 in words is "twenty million, thirteen thousand, five hundred twenty-three".