21523700016 has 240 divisors, whose sum is σ = 75652449600. Its totient is φ = 5676410880.

The previous prime is 21523699969. The next prime is 21523700047. The reversal of 21523700016 is 61000732512.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 625336 + ... + 658856.

It is an arithmetic number, because the mean of its divisors is an integer number (315218540).

Almost surely, 2^21523700016 is an apocalyptic number.

21523700016 is a gapful number since it is divisible by the number (26) 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 21523700016, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37826224800).

21523700016 is an abundant number, since it is smaller than the sum of its proper divisors (54128749584).

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

21523700016 is a wasteful number, since it uses less digits than its factorization.

21523700016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33569 (or 33546 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 27.

The spelling of 21523700016 in words is "twenty-one billion, five hundred twenty-three million, seven hundred thousand, sixteen".