21020221210 has 16 divisors (see below), whose sum is σ = 37871225856. Its totient is φ = 8400349008.

The previous prime is 21020221153. The next prime is 21020221259. The reversal of 21020221210 is 1212202012.

It is a happy number.

It is a super-3 number, since 3×21020221210³ (a number of 32 digits) contains 333 as substring.

It is an unprimeable number.

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, 956022 + ... + 977761.

It is an arithmetic number, because the mean of its divisors is an integer number (2366951616).

Almost surely, 2^21020221210 is an apocalyptic number.

21020221210 is a deficient number, since it is larger than the sum of its proper divisors (16851004646).

21020221210 is a wasteful number, since it uses less digits than its factorization.

21020221210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1934877.

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21020221210 its reverse (1212202012), we get a palindrome (22232423222).

The spelling of 21020221210 in words is "twenty-one billion, twenty million, two hundred twenty-one thousand, two hundred ten".