21506375272 has 16 divisors (see below), whose sum is σ = 42446793600. Its totient is φ = 10187230320.

The previous prime is 21506375257. The next prime is 21506375279. The reversal of 21506375272 is 27257360512.

It is not an unprimeable number, because it can be changed into a prime (21506375279) 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, 70744504 + ... + 70744807.

It is an arithmetic number, because the mean of its divisors is an integer number (2652924600).

Almost surely, 2^21506375272 is an apocalyptic number.

It is an amenable number.

21506375272 is a deficient number, since it is larger than the sum of its proper divisors (20940418328).

21506375272 is a wasteful number, since it uses less digits than its factorization.

21506375272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141489336 (or 141489332 counting only the distinct ones).

The product of its (nonzero) digits is 176400, while the sum is 40.

The spelling of 21506375272 in words is "twenty-one billion, five hundred six million, three hundred seventy-five thousand, two hundred seventy-two".