21020244170 has 16 divisors (see below), whose sum is σ = 37842069888. Its totient is φ = 8406846480.

The previous prime is 21020244169. The next prime is 21020244173. The reversal of 21020244170 is 7144202012.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21020244173) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 84254 + ... + 221673.

It is an arithmetic number, because the mean of its divisors is an integer number (2365129368).

Almost surely, 2^21020244170 is an apocalyptic number.

21020244170 is a deficient number, since it is larger than the sum of its proper divisors (16821825718).

21020244170 is a wasteful number, since it uses less digits than its factorization.

21020244170 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 312805.

The product of its (nonzero) digits is 896, while the sum is 23.

Adding to 21020244170 its reverse (7144202012), we get a palindrome (28164446182).

The spelling of 21020244170 in words is "twenty-one billion, twenty million, two hundred forty-four thousand, one hundred seventy".