21037500506 has 16 divisors (see below), whose sum is σ = 34441231968. Its totient is φ = 9557991600.

The previous prime is 21037500503. The next prime is 21037500559. The reversal of 21037500506 is 60500573012.

It is not an unprimeable number, because it can be changed into a prime (21037500503) 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, 177485 + ... + 271248.

It is an arithmetic number, because the mean of its divisors is an integer number (2152576998).

Almost surely, 2^21037500506 is an apocalyptic number.

21037500506 is a deficient number, since it is larger than the sum of its proper divisors (13403731462).

21037500506 is a wasteful number, since it uses less digits than its factorization.

21037500506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 450877.

The product of its (nonzero) digits is 6300, while the sum is 29.

The spelling of 21037500506 in words is "twenty-one billion, thirty-seven million, five hundred thousand, five hundred six".