20539666400 has 144 divisors (see below), whose sum is σ = 54779775120. Its totient is φ = 7458201600.

The previous prime is 20539666369. The next prime is 20539666429. The reversal of 20539666400 is 466693502.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8596406 + ... + 8598794.

It is an arithmetic number, because the mean of its divisors is an integer number (380415105).

Almost surely, 2^20539666400 is an apocalyptic number.

20539666400 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 20539666400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27389887560).

20539666400 is an abundant number, since it is smaller than the sum of its proper divisors (34240108720).

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

20539666400 is a wasteful number, since it uses less digits than its factorization.

20539666400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3397 (or 3384 counting only the distinct ones).

The product of its (nonzero) digits is 233280, while the sum is 41.

The spelling of 20539666400 in words is "twenty billion, five hundred thirty-nine million, six hundred sixty-six thousand, four hundred".