20906811 has 12 divisors (see below), whose sum is σ = 30270240. Its totient is φ = 13904880.

The previous prime is 20906807. The next prime is 20906819. The reversal of 20906811 is 11860902.

It is not a de Polignac number, because 20906811 - 2² = 20906807 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20906819) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1630 + ... + 6668.

It is an arithmetic number, because the mean of its divisors is an integer number (2522520).

Almost surely, 2^20906811 is an apocalyptic number.

20906811 is a deficient number, since it is larger than the sum of its proper divisors (9363429).

20906811 is a wasteful number, since it uses less digits than its factorization.

20906811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5506 (or 5503 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 27.

The square root of 20906811 is about 4572.3966363385. The cubic root of 20906811 is about 275.4837150550.

The spelling of 20906811 in words is "twenty million, nine hundred six thousand, eight hundred eleven".