21506088288 has 24 divisors (see below), whose sum is σ = 56453482008. Its totient is φ = 7168696064.

The previous prime is 21506088283. The next prime is 21506088293. The reversal of 21506088288 is 88288060512.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21506088283) and next prime (21506088293).

It is a tau number, because it is divible by the number of its divisors (24).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21506088283) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 112010781 + ... + 112010972.

It is an arithmetic number, because the mean of its divisors is an integer number (2352228417).

Almost surely, 2^21506088288 is an apocalyptic number.

It is an amenable number.

21506088288 is an abundant number, since it is smaller than the sum of its proper divisors (34947393720).

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

21506088288 is a wasteful number, since it uses less digits than its factorization.

21506088288 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 224021766 (or 224021758 counting only the distinct ones).

The product of its (nonzero) digits is 491520, while the sum is 48.

The spelling of 21506088288 in words is "twenty-one billion, five hundred six million, eighty-eight thousand, two hundred eighty-eight".