21957867468 has 54 divisors (see below), whose sum is σ = 56135993004. Its totient is φ = 7236955968.

The previous prime is 21957867457. The next prime is 21957867473. The reversal of 21957867468 is 86476875912.

21957867468 is a `hidden beast` number, since 2 + 1 + 95 + 7 + 86 + 7 + 468 = 666.

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 17 ways as a sum of consecutive naturals, for example, 246655 + ... + 323657.

It is an arithmetic number, because the mean of its divisors is an integer number (1039555426).

Almost surely, 2^21957867468 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21957867468, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28067996502).

21957867468 is an abundant number, since it is smaller than the sum of its proper divisors (34178125536).

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

21957867468 is a wasteful number, since it uses less digits than its factorization.

21957867468 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77191 (or 77097 counting only the distinct ones).

The product of its digits is 40642560, while the sum is 63.

The spelling of 21957867468 in words is "twenty-one billion, nine hundred fifty-seven million, eight hundred sixty-seven thousand, four hundred sixty-eight".