21641206250 has 24 divisors (see below), whose sum is σ = 40574676492. Its totient is φ = 8656480000.

The previous prime is 21641206241. The next prime is 21641206267. The reversal of 21641206250 is 5260214612.

It can be written as a sum of positive squares in 6 ways, for example, as 9549784729 + 12091421521 = 97723^2 + 109961^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1725047 + ... + 1737546.

Almost surely, 2^21641206250 is an apocalyptic number.

21641206250 is a deficient number, since it is larger than the sum of its proper divisors (18933470242).

21641206250 is an frugal number, since it uses more digits than its factorization.

21641206250 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3462620 (or 3462600 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 29.

The spelling of 21641206250 in words is "twenty-one billion, six hundred forty-one million, two hundred six thousand, two hundred fifty".