20640548 has 24 divisors (see below), whose sum is σ = 37330944. Its totient is φ = 9979200.

The previous prime is 20640541. The next prime is 20640553. The reversal of 20640548 is 84504602.

It is a self number, because there is not a number n which added to its sum of digits gives 20640548.

It is not an unprimeable number, because it can be changed into a prime (20640541) 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 in 7 ways as a sum of consecutive naturals, for example, 20333 + ... + 21323.

It is an arithmetic number, because the mean of its divisors is an integer number (1555456).

Almost surely, 2^20640548 is an apocalyptic number.

It is an amenable number.

20640548 is a deficient number, since it is larger than the sum of its proper divisors (16690396).

20640548 is a wasteful number, since it uses less digits than its factorization.

20640548 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1163 (or 1161 counting only the distinct ones).

The product of its (nonzero) digits is 7680, while the sum is 29.

The square root of 20640548 is about 4543.1869871270. The cubic root of 20640548 is about 274.3092216439.

The spelling of 20640548 in words is "twenty million, six hundred forty thousand, five hundred forty-eight".