20546640 has 60 divisors (see below), whose sum is σ = 69004884. Its totient is φ = 5478912.

The previous prime is 20546633. The next prime is 20546651. The reversal of 20546640 is 4664502.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 4769856 + 15776784 = 2184^2 + 3972^2 .

It is a tau number, because it is divible by the number of its divisors (60).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13549 + ... + 14988.

Almost surely, 2^20546640 is an apocalyptic number.

20546640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20546640 is an abundant number, since it is smaller than the sum of its proper divisors (48458244).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20546640 is a wasteful number, since it uses less digits than its factorization.

20546640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28556 (or 28547 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

The square root of 20546640 is about 4532.8401692537. The cubic root of 20546640 is about 273.8925822568.

The spelling of 20546640 in words is "twenty million, five hundred forty-six thousand, six hundred forty".