21500231670506 has 8 divisors (see below), whose sum is σ = 32267511081120. Its totient is φ = 10744394643468.

The previous prime is 21500231670503. The next prime is 21500231670557. The reversal of 21500231670506 is 60507613200512.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a self number, because there is not a number n which added to its sum of digits gives 21500231670506.

It is not an unprimeable number, because it can be changed into a prime (21500231670503) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2860591196 + ... + 2860598711.

It is an arithmetic number, because the mean of its divisors is an integer number (4033438885140).

Almost surely, 2^{21500231670506} is an apocalyptic number.

21500231670506 is a deficient number, since it is larger than the sum of its proper divisors (10767279410614).

21500231670506 is a wasteful number, since it uses less digits than its factorization.

21500231670506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5721191788.

The product of its (nonzero) digits is 75600, while the sum is 38.

The spelling of 21500231670506 in words is "twenty-one trillion, five hundred billion, two hundred thirty-one million, six hundred seventy thousand, five hundred six".