20987821326 has 16 divisors (see below), whose sum is σ = 42135249024. Its totient is φ = 6969339384.

The previous prime is 20987821303. The next prime is 20987821331. The reversal of 20987821326 is 62312878902.

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 7 ways as a sum of consecutive naturals, for example, 6648556 + ... + 6651711.

It is an arithmetic number, because the mean of its divisors is an integer number (2633453064).

Almost surely, 2^20987821326 is an apocalyptic number.

20987821326 is an abundant number, since it is smaller than the sum of its proper divisors (21147427698).

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

20987821326 is a wasteful number, since it uses less digits than its factorization.

20987821326 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13300535.

The product of its (nonzero) digits is 580608, while the sum is 48.

The spelling of 20987821326 in words is "twenty billion, nine hundred eighty-seven million, eight hundred twenty-one thousand, three hundred twenty-six".