20101221210 has 64 divisors (see below), whose sum is σ = 55174079232. Its totient is φ = 4591289856.

The previous prime is 20101221193. The next prime is 20101221271. The reversal of 20101221210 is 1212210102.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 267532 + ... + 334328.

It is an arithmetic number, because the mean of its divisors is an integer number (862094988).

Almost surely, 2^20101221210 is an apocalyptic number.

20101221210 is an abundant number, since it is smaller than the sum of its proper divisors (35072858022).

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

20101221210 is a wasteful number, since it uses less digits than its factorization.

20101221210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68247.

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 20101221210 its reverse (1212210102), we get a palindrome (21313431312).

It can be divided in two parts, 201012 and 21210, that added together give a palindrome (222222).

The spelling of 20101221210 in words is "twenty billion, one hundred one million, two hundred twenty-one thousand, two hundred ten".