21242450525 has 12 divisors (see below), whose sum is σ = 26586816192. Its totient is φ = 16835136240.

The previous prime is 21242450501. The next prime is 21242450549. The reversal of 21242450525 is 52505424212.

It is an interprime number because it is at equal distance from previous prime (21242450501) and next prime (21242450549).

It is not a de Polignac number, because 21242450525 - 2⁶ = 21242450461 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21242450491 and 21242450500.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3967877 + ... + 3973226.

It is an arithmetic number, because the mean of its divisors is an integer number (2215568016).

Almost surely, 2^21242450525 is an apocalyptic number.

21242450525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21242450525 is a deficient number, since it is larger than the sum of its proper divisors (5344365667).

21242450525 is a wasteful number, since it uses less digits than its factorization.

21242450525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7941220 (or 7941215 counting only the distinct ones).

The product of its (nonzero) digits is 32000, while the sum is 32.

Adding to 21242450525 its reverse (52505424212), we get a palindrome (73747874737).

The spelling of 21242450525 in words is "twenty-one billion, two hundred forty-two million, four hundred fifty thousand, five hundred twenty-five".