20257609680 has 640 divisors, whose sum is σ = 89822822400. Its totient is φ = 4072550400.

The previous prime is 20257609663. The next prime is 20257609733. The reversal of 20257609680 is 8690675202.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

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 127 ways as a sum of consecutive naturals, for example, 5153956 + ... + 5157884.

It is an arithmetic number, because the mean of its divisors is an integer number (140348160).

Almost surely, 2^20257609680 is an apocalyptic number.

20257609680 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20257609680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44911411200).

20257609680 is an abundant number, since it is smaller than the sum of its proper divisors (69565212720).

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

20257609680 is a wasteful number, since it uses less digits than its factorization.

20257609680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4000 (or 3988 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 45.

The spelling of 20257609680 in words is "twenty billion, two hundred fifty-seven million, six hundred nine thousand, six hundred eighty".