20534 has 4 divisors (see below), whose sum is σ = 30804. Its totient is φ = 10266.

The previous prime is 20533. The next prime is 20543. The reversal of 20534 is 43502.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 43502 = 2 ⋅21751.

It is a plaindrome in base 11.

It is a nialpdrome in base 12.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20533) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5132 + ... + 5135.

It is an arithmetic number, because the mean of its divisors is an integer number (7701).

2²⁰⁵³⁴ is an apocalyptic number.

20534 is a deficient number, since it is larger than the sum of its proper divisors (10270).

20534 is a wasteful number, since it uses less digits than its factorization.

20534 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10269.

The product of its (nonzero) digits is 120, while the sum is 14.

The square root of 20534 is about 143.2968945930. The cubic root of 20534 is about 27.3836405798.

The spelling of 20534 in words is "twenty thousand, five hundred thirty-four".