21203254525 has 24 divisors (see below), whose sum is σ = 26915848704. Its totient is φ = 16561876800.

The previous prime is 21203254507. The next prime is 21203254531. The reversal of 21203254525 is 52545230212.

It is not a de Polignac number, because 21203254525 - 2¹⁷ = 21203123453 is a prime.

It is a congruent number.

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, 473244 + ... + 516106.

It is an arithmetic number, because the mean of its divisors is an integer number (1121493696).

Almost surely, 2^21203254525 is an apocalyptic number.

21203254525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21203254525 is a deficient number, since it is larger than the sum of its proper divisors (5712594179).

21203254525 is a wasteful number, since it uses less digits than its factorization.

21203254525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43341 (or 43336 counting only the distinct ones).

The product of its (nonzero) digits is 24000, while the sum is 31.

Adding to 21203254525 its reverse (52545230212), we get a palindrome (73748484737).

The spelling of 21203254525 in words is "twenty-one billion, two hundred three million, two hundred fifty-four thousand, five hundred twenty-five".