21247702588 has 24 divisors (see below), whose sum is σ = 44343032832. Its totient is φ = 8710238064.

The previous prime is 21247702583. The next prime is 21247702589. The reversal of 21247702588 is 88520774212.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (46).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21247702583) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 16496020 + ... + 16497307.

It is an arithmetic number, because the mean of its divisors is an integer number (1847626368).

Almost surely, 2^21247702588 is an apocalyptic number.

21247702588 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21247702588 is an abundant number, since it is smaller than the sum of its proper divisors (23095330244).

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

21247702588 is a wasteful number, since it uses less digits than its factorization.

21247702588 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32993361 (or 32993359 counting only the distinct ones).

The product of its (nonzero) digits is 501760, while the sum is 46.

The spelling of 21247702588 in words is "twenty-one billion, two hundred forty-seven million, seven hundred two thousand, five hundred eighty-eight".