20396977128 has 384 divisors, whose sum is σ = 68173747200. Its totient is φ = 5428684800.

The previous prime is 20396977099. The next prime is 20396977141. The reversal of 20396977128 is 82177969302.

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 95 ways as a sum of consecutive naturals, for example, 18162375 + ... + 18163497.

It is an arithmetic number, because the mean of its divisors is an integer number (177535800).

Almost surely, 2^20396977128 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 20396977128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34086873600).

20396977128 is an abundant number, since it is smaller than the sum of its proper divisors (47776770072).

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

20396977128 is a wasteful number, since it uses less digits than its factorization.

20396977128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1253 (or 1246 counting only the distinct ones).

The product of its (nonzero) digits is 2286144, while the sum is 54.

The spelling of 20396977128 in words is "twenty billion, three hundred ninety-six million, nine hundred seventy-seven thousand, one hundred twenty-eight".