20121443225 has 24 divisors (see below), whose sum is σ = 27310382232. Its totient is φ = 14615308800.

The previous prime is 20121443191. The next prime is 20121443233. The reversal of 20121443225 is 52234412102.

It can be written as a sum of positive squares in 12 ways, for example, as 11078194009 + 9043249216 = 105253^2 + 95096^2 .

It is not a de Polignac number, because 20121443225 - 2⁶ = 20121443161 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 20121443194 and 20121443203.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 487652 + ... + 527301.

It is an arithmetic number, because the mean of its divisors is an integer number (1137932593).

Almost surely, 2^20121443225 is an apocalyptic number.

20121443225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20121443225 is a deficient number, since it is larger than the sum of its proper divisors (7188939007).

20121443225 is a wasteful number, since it uses less digits than its factorization.

20121443225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1015037 (or 1015032 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 26.

Adding to 20121443225 its reverse (52234412102), we get a palindrome (72355855327).

The spelling of 20121443225 in words is "twenty billion, one hundred twenty-one million, four hundred forty-three thousand, two hundred twenty-five".