20309121408 has 64 divisors (see below), whose sum is σ = 54469958400. Its totient is φ = 6703968768.

The previous prime is 20309121379. The next prime is 20309121433. The reversal of 20309121408 is 80412190302.

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 217188 + ... + 296291.

It is an arithmetic number, because the mean of its divisors is an integer number (851093100).

Almost surely, 2^20309121408 is an apocalyptic number.

It is an amenable number.

20309121408 is an abundant number, since it is smaller than the sum of its proper divisors (34160836992).

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

20309121408 is a wasteful number, since it uses less digits than its factorization.

20309121408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 513599 (or 513587 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 30.

The spelling of 20309121408 in words is "twenty billion, three hundred nine million, one hundred twenty-one thousand, four hundred eight".