20997948967424 has 320 divisors, whose sum is σ = 52696059736320. Its totient is φ = 8211517931520.

The previous prime is 20997948967399. The next prime is 20997948967453. The reversal of 20997948967424 is 42476984979902.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 128119322 + ... + 128283110.

It is an arithmetic number, because the mean of its divisors is an integer number (164675186676).

Almost surely, 2^{20997948967424} 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 20997948967424, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26348029868160).

20997948967424 is an abundant number, since it is smaller than the sum of its proper divisors (31698110768896).

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

20997948967424 is a wasteful number, since it uses less digits than its factorization.

20997948967424 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 163951 (or 163935 counting only the distinct ones).

The product of its (nonzero) digits is 3950456832, while the sum is 80.

The spelling of 20997948967424 in words is "twenty trillion, nine hundred ninety-seven billion, nine hundred forty-eight million, nine hundred sixty-seven thousand, four hundred twenty-four".