11211001220 has 24 divisors (see below), whose sum is σ = 24927991704. Its totient is φ = 4220612096.

The previous prime is 11211001213. The next prime is 11211001247. The reversal of 11211001220 is 2210011211.

It can be written as a sum of positive squares in 4 ways, for example, as 5414310724 + 5796690496 = 73582^2 + 76136^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16486427 + ... + 16487106.

It is an arithmetic number, because the mean of its divisors is an integer number (1038666321).

Almost surely, 2^11211001220 is an apocalyptic number.

11211001220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

11211001220 is an abundant number, since it is smaller than the sum of its proper divisors (13716990484).

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

11211001220 is a wasteful number, since it uses less digits than its factorization.

11211001220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32973559 (or 32973557 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 11211001220 its reverse (2210011211), we get a palindrome (13421012431).

Subtracting from 11211001220 its reverse (2210011211), we obtain a palindrome (9000990009).

The spelling of 11211001220 in words is "eleven billion, two hundred eleven million, one thousand, two hundred twenty".