20645744 has 20 divisors (see below), whose sum is σ = 45715824. Its totient is φ = 8848128.

The previous prime is 20645711. The next prime is 20645749. The reversal of 20645744 is 44754602.

It is a self number, because there is not a number n which added to its sum of digits gives 20645744.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20645749) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 92057 + ... + 92280.

Almost surely, 2^20645744 is an apocalyptic number.

It is an amenable number.

20645744 is an abundant number, since it is smaller than the sum of its proper divisors (25070080).

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

20645744 is a wasteful number, since it uses less digits than its factorization.

20645744 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 184352 (or 184346 counting only the distinct ones).

The product of its (nonzero) digits is 26880, while the sum is 32.

The square root of 20645744 is about 4543.7587964151. The cubic root of 20645744 is about 274.3322376855.

The spelling of 20645744 in words is "twenty million, six hundred forty-five thousand, seven hundred forty-four".