20238704640 has 1344 divisors, whose sum is σ = 94215094272. Its totient is φ = 3892838400.

The previous prime is 20238704611. The next prime is 20238704719. The reversal of 20238704640 is 4640783202.

20238704640 is a `hidden beast` number, since 2 + 0 + 2 + 3 + 8 + 7 + 0 + 4 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (1344).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 20238704595 and 20238704604.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 652861425 + ... + 652861455.

Almost surely, 2^20238704640 is an apocalyptic number.

20238704640 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 20238704640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47107547136).

20238704640 is an abundant number, since it is smaller than the sum of its proper divisors (73976389632).

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

20238704640 is a wasteful number, since it uses less digits than its factorization.

20238704640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109 (or 82 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 36.

The spelling of 20238704640 in words is "twenty billion, two hundred thirty-eight million, seven hundred four thousand, six hundred forty".