20121200420 has 12 divisors (see below), whose sum is σ = 42254520924. Its totient is φ = 8048480160.

The previous prime is 20121200417. The next prime is 20121200461. The reversal of 20121200420 is 2400212102.

It can be written as a sum of positive squares in 2 ways, for example, as 2240696896 + 17880503524 = 47336^2 + 133718^2 .

It is a junction number, because it is equal to n+sod(n) for n = 20121200395 and 20121200404.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 503029991 + ... + 503030030.

It is an arithmetic number, because the mean of its divisors is an integer number (3521210077).

Almost surely, 2^20121200420 is an apocalyptic number.

20121200420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20121200420 is an abundant number, since it is smaller than the sum of its proper divisors (22133320504).

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

20121200420 is a wasteful number, since it uses less digits than its factorization.

20121200420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1006060030 (or 1006060028 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 14.

Adding to 20121200420 its reverse (2400212102), we get a palindrome (22521412522).

The spelling of 20121200420 in words is "twenty billion, one hundred twenty-one million, two hundred thousand, four hundred twenty".