20021238720 has 896 divisors, whose sum is σ = 86729011200. Its totient is φ = 4248059904.

The previous prime is 20021238709. The next prime is 20021238739. The reversal of 20021238720 is 2783212002.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 51468286 + ... + 51468674.

Almost surely, 2^20021238720 is an apocalyptic number.

20021238720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20021238720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43364505600).

20021238720 is an abundant number, since it is smaller than the sum of its proper divisors (66707772480).

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

20021238720 is a wasteful number, since it uses less digits than its factorization.

20021238720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 482 (or 466 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The spelling of 20021238720 in words is "twenty billion, twenty-one million, two hundred thirty-eight thousand, seven hundred twenty".