20155234220 has 48 divisors (see below), whose sum is σ = 47421769248. Its totient is φ = 7131087360.

The previous prime is 20155234193. The next prime is 20155234243. The reversal of 20155234220 is 2243255102.

It is a self number, because there is not a number n which added to its sum of digits gives 20155234220.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1229897 + ... + 1246176.

It is an arithmetic number, because the mean of its divisors is an integer number (987953526).

Almost surely, 2^20155234220 is an apocalyptic number.

20155234220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20155234220 is an abundant number, since it is smaller than the sum of its proper divisors (27266535028).

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

20155234220 is a wasteful number, since it uses less digits than its factorization.

20155234220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2476130 (or 2476128 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 26.

Adding to 20155234220 its reverse (2243255102), we get a palindrome (22398489322).

The spelling of 20155234220 in words is "twenty billion, one hundred fifty-five million, two hundred thirty-four thousand, two hundred twenty".