21945219210 has 48 divisors (see below), whose sum is σ = 57376369440. Its totient is φ = 5819361120.

The previous prime is 21945219161. The next prime is 21945219211. The reversal of 21945219210 is 1291254912.

21945219210 is a `hidden beast` number, since 2 + 1 + 9 + 452 + 192 + 10 = 666.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21945219211) 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, 664996 + ... + 697215.

It is an arithmetic number, because the mean of its divisors is an integer number (1195341030).

Almost surely, 2^21945219210 is an apocalyptic number.

21945219210 is an abundant number, since it is smaller than the sum of its proper divisors (35431150230).

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

21945219210 is a wasteful number, since it uses less digits than its factorization.

21945219210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1362403 (or 1362400 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The spelling of 21945219210 in words is "twenty-one billion, nine hundred forty-five million, two hundred nineteen thousand, two hundred ten".