21435520125 has 32 divisors (see below), whose sum is σ = 35925402240. Its totient is φ = 11350003200.

The previous prime is 21435520091. The next prime is 21435520129. The reversal of 21435520125 is 52102553412.

It is not a de Polignac number, because 21435520125 - 2¹¹ = 21435518077 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21435520092 and 21435520101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21435520129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 153492 + ... + 257741.

It is an arithmetic number, because the mean of its divisors is an integer number (1122668820).

Almost surely, 2^21435520125 is an apocalyptic number.

21435520125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21435520125 is a deficient number, since it is larger than the sum of its proper divisors (14489882115).

21435520125 is a wasteful number, since it uses less digits than its factorization.

21435520125 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 411390 (or 411380 counting only the distinct ones).

The product of its (nonzero) digits is 12000, while the sum is 30.

The spelling of 21435520125 in words is "twenty-one billion, four hundred thirty-five million, five hundred twenty thousand, one hundred twenty-five".