2311211220 has 24 divisors (see below), whose sum is σ = 6471391584. Its totient is φ = 616322976.

The previous prime is 2311211207. The next prime is 2311211237. The reversal of 2311211220 is 221121132.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 2311211220.

It is a congruent number.

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, 19260034 + ... + 19260153.

It is an arithmetic number, because the mean of its divisors is an integer number (269641316).

Almost surely, 2^2311211220 is an apocalyptic number.

2311211220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2311211220 is an abundant number, since it is smaller than the sum of its proper divisors (4160180364).

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

2311211220 is a wasteful number, since it uses less digits than its factorization.

2311211220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38520199 (or 38520197 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 15.

The square root of 2311211220 is about 48075.0581902924. The cubic root of 2311211220 is about 1322.1474114342.

Adding to 2311211220 its reverse (221121132), we get a palindrome (2532332352).

It can be divided in two parts, 2311 and 211220, that added together give a triangular number (213531 = T₆₅₃).

The spelling of 2311211220 in words is "two billion, three hundred eleven million, two hundred eleven thousand, two hundred twenty".