21247370550 has 768 divisors, whose sum is σ = 74395238400. Its totient is φ = 4354560000.

The previous prime is 21247370531. The next prime is 21247370563. The reversal of 21247370550 is 5507374212.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 348317520 + ... + 348317580.

It is an arithmetic number, because the mean of its divisors is an integer number (96868800).

Almost surely, 2^21247370550 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21247370550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37197619200).

21247370550 is an abundant number, since it is smaller than the sum of its proper divisors (53147867850).

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

21247370550 is a wasteful number, since it uses less digits than its factorization.

21247370550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 190 (or 179 counting only the distinct ones).

The product of its (nonzero) digits is 58800, while the sum is 36.

The spelling of 21247370550 in words is "twenty-one billion, two hundred forty-seven million, three hundred seventy thousand, five hundred fifty".