20534531 has 2 divisors, whose sum is σ = 20534532. Its totient is φ = 20534530.

The previous prime is 20534489. The next prime is 20534533. The reversal of 20534531 is 13543502.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20534531 - 2⁶ = 20534467 is a prime.

It is a super-2 number, since 2×20534531² = 843333926779922, which contains 22 as substring.

Together with 20534533, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 20534497 and 20534506.

It is not a weakly prime, because it can be changed into another prime (20534533) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10267265 + 10267266.

It is an arithmetic number, because the mean of its divisors is an integer number (10267266).

Almost surely, 2^20534531 is an apocalyptic number.

20534531 is a deficient number, since it is larger than the sum of its proper divisors (1).

20534531 is an equidigital number, since it uses as much as digits as its factorization.

20534531 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1800, while the sum is 23.

The square root of 20534531 is about 4531.5042756242. The cubic root of 20534531 is about 273.8387662067.

The spelling of 20534531 in words is "twenty million, five hundred thirty-four thousand, five hundred thirty-one".