20851968480 has 96 divisors (see below), whose sum is σ = 75067098624. Its totient is φ = 4766163456.

The previous prime is 20851968479. The next prime is 20851968497. The reversal of 20851968480 is 8486915802.

It is a tau number, because it is divible by the number of its divisors (96).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3099612 + ... + 3106331.

It is an arithmetic number, because the mean of its divisors is an integer number (781948944).

Almost surely, 2^20851968480 is an apocalyptic number.

20851968480 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20851968480 is an abundant number, since it is smaller than the sum of its proper divisors (54215130144).

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

20851968480 is a wasteful number, since it uses less digits than its factorization.

20851968480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6205968 (or 6205960 counting only the distinct ones).

The product of its (nonzero) digits is 1105920, while the sum is 51.

The spelling of 20851968480 in words is "twenty billion, eight hundred fifty-one million, nine hundred sixty-eight thousand, four hundred eighty".