20757845 has 8 divisors (see below), whose sum is σ = 25992576. Its totient is φ = 15884176.

The previous prime is 20757809. The next prime is 20757853. The reversal of 20757845 is 54875702.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20757845 - 2⁸ = 20757589 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20757799 and 20757808.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 90137 + ... + 90366.

It is an arithmetic number, because the mean of its divisors is an integer number (3249072).

Almost surely, 2^20757845 is an apocalyptic number.

It is an amenable number.

20757845 is a deficient number, since it is larger than the sum of its proper divisors (5234731).

20757845 is a wasteful number, since it uses less digits than its factorization.

20757845 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 180531.

The product of its (nonzero) digits is 78400, while the sum is 38.

The square root of 20757845 is about 4556.0778088176. The cubic root of 20757845 is about 274.8278592103.

The spelling of 20757845 in words is "twenty million, seven hundred fifty-seven thousand, eight hundred forty-five".