20123543 has 16 divisors (see below), whose sum is σ = 22619520. Its totient is φ = 17748000.

The previous prime is 20123539. The next prime is 20123549. The reversal of 20123543 is 34532102.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 20123543 - 2² = 20123539 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20123549) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 65396 + ... + 65702.

It is an arithmetic number, because the mean of its divisors is an integer number (1413720).

Almost surely, 2^20123543 is an apocalyptic number.

20123543 is a deficient number, since it is larger than the sum of its proper divisors (2495977).

20123543 is a wasteful number, since it uses less digits than its factorization.

20123543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 478.

The product of its (nonzero) digits is 720, while the sum is 20.

The square root of 20123543 is about 4485.9272174212. The cubic root of 20123543 is about 271.9995269239. Note that the first 3 decimals are identical.

Adding to 20123543 its reverse (34532102), we get a palindrome (54655645).

It can be divided in two parts, 2012 and 3543, that added together give a palindrome (5555).

The spelling of 20123543 in words is "twenty million, one hundred twenty-three thousand, five hundred forty-three".