21536149504 has 39 divisors (see below), whose sum is σ = 43085831313. Its totient is φ = 10763378688.

The previous prime is 21536149501. The next prime is 21536149511. The reversal of 21536149504 is 40594163512.

The square root of 21536149504 is 146752.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 6247321600 + 15288827904 = 79040^2 + 123648^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21536149501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 9390982 + ... + 9393274.

Almost surely, 2^21536149504 is an apocalyptic number.

21536149504 is the 146752-nd square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21536149504

21536149504 is an abundant number, since it is smaller than the sum of its proper divisors (21549681809).

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

21536149504 is an frugal number, since it uses more digits than its factorization.

21536149504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4610 (or 2295 counting only the distinct ones).

The product of its (nonzero) digits is 129600, while the sum is 40.

The spelling of 21536149504 in words is "twenty-one billion, five hundred thirty-six million, one hundred forty-nine thousand, five hundred four".