20356668 has 18 divisors (see below), whose sum is σ = 51457224. Its totient is φ = 6785544.

The previous prime is 20356639. The next prime is 20356709. The reversal of 20356668 is 86665302.

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 565463 = 20356668 / (2 + 0 + 3 + 5 + 6 + 6 + 6 + 8).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 282696 + ... + 282767.

Almost surely, 2^20356668 is an apocalyptic number.

It is an amenable number.

20356668 is an abundant number, since it is smaller than the sum of its proper divisors (31100556).

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

20356668 is a wasteful number, since it uses less digits than its factorization.

20356668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 565473 (or 565468 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The square root of 20356668 is about 4511.8364332054. The cubic root of 20356668 is about 273.0458402274.

The spelling of 20356668 in words is "twenty million, three hundred fifty-six thousand, six hundred sixty-eight".