20393720 has 16 divisors (see below), whose sum is σ = 45885960. Its totient is φ = 8157472.

The previous prime is 20393717. The next prime is 20393729. The reversal of 20393720 is 2739302.

It is a self number, because there is not a number n which added to its sum of digits gives 20393720.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20393729) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 254882 + ... + 254961.

Almost surely, 2^20393720 is an apocalyptic number.

20393720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20393720 is an abundant number, since it is smaller than the sum of its proper divisors (25492240).

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

20393720 is a wasteful number, since it uses less digits than its factorization.

20393720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 509854 (or 509850 counting only the distinct ones).

The product of its (nonzero) digits is 2268, while the sum is 26.

The square root of 20393720 is about 4515.9406550574. The cubic root of 20393720 is about 273.2114004362.

The spelling of 20393720 in words is "twenty million, three hundred ninety-three thousand, seven hundred twenty".