20393656 has 8 divisors (see below), whose sum is σ = 38238120. Its totient is φ = 10196824.

The previous prime is 20393651. The next prime is 20393677. The reversal of 20393656 is 65639302.

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-3 number, since 3×20393656³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20393651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1274596 + ... + 1274611.

It is an arithmetic number, because the mean of its divisors is an integer number (4779765).

Almost surely, 2^20393656 is an apocalyptic number.

It is an amenable number.

20393656 is a deficient number, since it is larger than the sum of its proper divisors (17844464).

20393656 is a wasteful number, since it uses less digits than its factorization.

20393656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2549213 (or 2549209 counting only the distinct ones).

The product of its (nonzero) digits is 29160, while the sum is 34.

The square root of 20393656 is about 4515.9335690420. The cubic root of 20393656 is about 273.2111146366.

The spelling of 20393656 in words is "twenty million, three hundred ninety-three thousand, six hundred fifty-six".