20297396856 has 128 divisors (see below), whose sum is σ = 56604925440. Its totient is φ = 6012864000.

The previous prime is 20297396851. The next prime is 20297396863. The reversal of 20297396856 is 65869379202.

It is a junction number, because it is equal to n+sod(n) for n = 20297396796 and 20297396805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20297396851) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4097181 + ... + 4102131.

It is an arithmetic number, because the mean of its divisors is an integer number (442225980).

Almost surely, 2^20297396856 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 20297396856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28302462720).

20297396856 is an abundant number, since it is smaller than the sum of its proper divisors (36307528584).

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

20297396856 is a wasteful number, since it uses less digits than its factorization.

20297396856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5317 (or 5313 counting only the distinct ones).

The product of its (nonzero) digits is 9797760, while the sum is 57.

The spelling of 20297396856 in words is "twenty billion, two hundred ninety-seven million, three hundred ninety-six thousand, eight hundred fifty-six".