21502435125425 has 12 divisors (see below), whose sum is σ = 28231432471116. Its totient is φ = 16190068800000.

The previous prime is 21502435125419. The next prime is 21502435125427. The reversal of 21502435125425 is 52452153420512.

21502435125425 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 6 ways, for example, as 2308117524001 + 19194317601424 = 1519249^2 + 4381132^2 .

It is not a de Polignac number, because 21502435125425 - 2⁶ = 21502435125361 is a prime.

It is a super-2 number, since 2×21502435125425² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21502435125427) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 25296982076 + ... + 25296982925.

It is an arithmetic number, because the mean of its divisors is an integer number (2352619372593).

Almost surely, 2^{21502435125425} is an apocalyptic number.

21502435125425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21502435125425 is a deficient number, since it is larger than the sum of its proper divisors (6728997345691).

21502435125425 is a wasteful number, since it uses less digits than its factorization.

21502435125425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50593965028 (or 50593965023 counting only the distinct ones).

The product of its (nonzero) digits is 480000, while the sum is 41.

Adding to 21502435125425 its reverse (52452153420512), we get a palindrome (73954588545937).

The spelling of 21502435125425 in words is "twenty-one trillion, five hundred two billion, four hundred thirty-five million, one hundred twenty-five thousand, four hundred twenty-five".