20945685 has 32 divisors (see below), whose sum is σ = 34992000. Its totient is φ = 10685696.

The previous prime is 20945651. The next prime is 20945693. The reversal of 20945685 is 58654902.

It is a cyclic number.

It is not a de Polignac number, because 20945685 - 2⁶ = 20945621 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 77731 + ... + 77999.

It is an arithmetic number, because the mean of its divisors is an integer number (1093500).

Almost surely, 2^20945685 is an apocalyptic number.

It is an amenable number.

20945685 is a deficient number, since it is larger than the sum of its proper divisors (14046315).

20945685 is a wasteful number, since it uses less digits than its factorization.

20945685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 485.

The product of its (nonzero) digits is 86400, while the sum is 39.

The square root of 20945685 is about 4576.6456056811. The cubic root of 20945685 is about 275.6543535976.

The spelling of 20945685 in words is "twenty million, nine hundred forty-five thousand, six hundred eighty-five".