20123787840 has 224 divisors, whose sum is σ = 68948052096. Its totient is φ = 4943462400.

The previous prime is 20123787833. The next prime is 20123787899. The reversal of 20123787840 is 4878732102.

It is a junction number, because it is equal to n+sod(n) for n = 20123787792 and 20123787801.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7499139 + ... + 7501821.

It is an arithmetic number, because the mean of its divisors is an integer number (307803804).

Almost surely, 2^20123787840 is an apocalyptic number.

20123787840 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 20123787840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34474026048).

20123787840 is an abundant number, since it is smaller than the sum of its proper divisors (48824264256).

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

20123787840 is a wasteful number, since it uses less digits than its factorization.

20123787840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3317 (or 3307 counting only the distinct ones).

The product of its (nonzero) digits is 150528, while the sum is 42.

The spelling of 20123787840 in words is "twenty billion, one hundred twenty-three million, seven hundred eighty-seven thousand, eight hundred forty".