21111354525 has 24 divisors (see below), whose sum is σ = 34908633760. Its totient is φ = 11257928640.

The previous prime is 21111354503. The next prime is 21111354533. The reversal of 21111354525 is 52545311112.

It is not a de Polignac number, because 21111354525 - 2⁵ = 21111354493 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21111354492 and 21111354501.

It is a congruent number.

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 816699 + ... + 842151.

Almost surely, 2^21111354525 is an apocalyptic number.

21111354525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21111354525 is a deficient number, since it is larger than the sum of its proper divisors (13797279235).

21111354525 is a wasteful number, since it uses less digits than its factorization.

21111354525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36525 (or 36520 counting only the distinct ones).

The product of its digits is 6000, while the sum is 30.

Adding to 21111354525 its reverse (52545311112), we get a palindrome (73656665637).

The spelling of 21111354525 in words is "twenty-one billion, one hundred eleven million, three hundred fifty-four thousand, five hundred twenty-five".