20543654 has 4 divisors (see below), whose sum is σ = 30815484. Its totient is φ = 10271826.

The previous prime is 20543639. The next prime is 20543657. The reversal of 20543654 is 45634502.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 45634502 = 2 ⋅22817251.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20543657) 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, 5135912 + ... + 5135915.

It is an arithmetic number, because the mean of its divisors is an integer number (7703871).

Almost surely, 2^20543654 is an apocalyptic number.

20543654 is a deficient number, since it is larger than the sum of its proper divisors (10271830).

20543654 is a wasteful number, since it uses less digits than its factorization.

20543654 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10271829.

The product of its (nonzero) digits is 14400, while the sum is 29.

The square root of 20543654 is about 4532.5107832194. The cubic root of 20543654 is about 273.8793135363.

The spelling of 20543654 in words is "twenty million, five hundred forty-three thousand, six hundred fifty-four".