21173396650 has 48 divisors (see below), whose sum is σ = 45857850624. Its totient is φ = 7122473280.

The previous prime is 21173396599. The next prime is 21173396653. The reversal of 21173396650 is 5669337112.

It is a Smith number, since the sum of its digits (43) coincides with the sum of the digits of its prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 21173396597 and 21173396606.

It is not an unprimeable number, because it can be changed into a prime (21173396653) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 552162 + ... + 589261.

It is an arithmetic number, because the mean of its divisors is an integer number (955371888).

Almost surely, 2^21173396650 is an apocalyptic number.

21173396650 is an abundant number, since it is smaller than the sum of its proper divisors (24684453974).

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

21173396650 is a wasteful number, since it uses less digits than its factorization.

21173396650 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1141495 (or 1141490 counting only the distinct ones).

The product of its (nonzero) digits is 204120, while the sum is 43.

The spelling of 21173396650 in words is "twenty-one billion, one hundred seventy-three million, three hundred ninety-six thousand, six hundred fifty".