20640623850 has 768 divisors, whose sum is σ = 75595161600. Its totient is φ = 4015872000.

The previous prime is 20640623833. The next prime is 20640623953. The reversal of 20640623850 is 5832604602.

20640623850 is a `hidden beast` number, since 2 + 0 + 640 + 6 + 2 + 3 + 8 + 5 + 0 = 666.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 123596467 + ... + 123596633.

It is an arithmetic number, because the mean of its divisors is an integer number (98431200).

Almost surely, 2^20640623850 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20640623850, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37797580800).

20640623850 is an abundant number, since it is smaller than the sum of its proper divisors (54954537750).

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

20640623850 is a wasteful number, since it uses less digits than its factorization.

20640623850 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 276 (or 265 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 36.

The spelling of 20640623850 in words is "twenty billion, six hundred forty million, six hundred twenty-three thousand, eight hundred fifty".