21012382537 has 16 divisors (see below), whose sum is σ = 21694464000. Its totient is φ = 20339463312.

The previous prime is 21012382529. The next prime is 21012382579. The reversal of 21012382537 is 73528321012.

It is a cyclic number.

It is not a de Polignac number, because 21012382537 - 2³ = 21012382529 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21012302537) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 7004964 + ... + 7007962.

It is an arithmetic number, because the mean of its divisors is an integer number (1355904000).

Almost surely, 2^21012382537 is an apocalyptic number.

It is an amenable number.

21012382537 is a deficient number, since it is larger than the sum of its proper divisors (682081463).

21012382537 is a wasteful number, since it uses less digits than its factorization.

21012382537 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4452.

The product of its (nonzero) digits is 20160, while the sum is 34.

The spelling of 21012382537 in words is "twenty-one billion, twelve million, three hundred eighty-two thousand, five hundred thirty-seven".