21989172802010 has 16 divisors (see below), whose sum is σ = 39581816112072. Its totient is φ = 8795379105600.

The previous prime is 21989172801929. The next prime is 21989172802013. The reversal of 21989172802010 is 1020827198912.

It can be written as a sum of positive squares in 4 ways, for example, as 20283502845841 + 1705669956169 = 4503721^2 + 1306013^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21989172802010.

It is not an unprimeable number, because it can be changed into a prime (21989172802013) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35933321 + ... + 36540140.

Almost surely, 2^{21989172802010} is an apocalyptic number.

21989172802010 is a deficient number, since it is larger than the sum of its proper divisors (17592643310062).

21989172802010 is a wasteful number, since it uses less digits than its factorization.

21989172802010 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72503809.

The product of its (nonzero) digits is 290304, while the sum is 50.

The spelling of 21989172802010 in words is "twenty-one trillion, nine hundred eighty-nine billion, one hundred seventy-two million, eight hundred two thousand, ten".