21173660250 has 32 divisors (see below), whose sum is σ = 52849457856. Its totient is φ = 5646309200.

The previous prime is 21173660239. The next prime is 21173660267. The reversal of 21173660250 is 5206637112.

It is an unprimeable number.

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, 14115024 + ... + 14116523.

It is an arithmetic number, because the mean of its divisors is an integer number (1651545558).

Almost surely, 2^21173660250 is an apocalyptic number.

21173660250 is an abundant number, since it is smaller than the sum of its proper divisors (31675797606).

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

21173660250 is a wasteful number, since it uses less digits than its factorization.

21173660250 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28231567 (or 28231557 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 33.

The spelling of 21173660250 in words is "twenty-one billion, one hundred seventy-three million, six hundred sixty thousand, two hundred fifty".