20209373856 has 384 divisors, whose sum is σ = 68929781760. Its totient is φ = 5641767936.

The previous prime is 20209373831. The next prime is 20209373887. The reversal of 20209373856 is 65837390202.

20209373856 is a `hidden beast` number, since 20 + 209 + 373 + 8 + 56 = 666.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 63751810 + ... + 63752126.

It is an arithmetic number, because the mean of its divisors is an integer number (179504640).

Almost surely, 2^20209373856 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20209373856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34464890880).

20209373856 is an abundant number, since it is smaller than the sum of its proper divisors (48720407904).

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

20209373856 is a wasteful number, since it uses less digits than its factorization.

20209373856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 553 (or 539 counting only the distinct ones).

The product of its (nonzero) digits is 544320, while the sum is 45.

The spelling of 20209373856 in words is "twenty billion, two hundred nine million, three hundred seventy-three thousand, eight hundred fifty-six".