21000302523 has 12 divisors (see below), whose sum is σ = 30386901688. Its totient is φ = 13975679520.

The previous prime is 21000302497. The next prime is 21000302567. The reversal of 21000302523 is 32520300012.

It is not a de Polignac number, because 21000302523 - 2³⁰ = 19926560699 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21000302496 and 21000302505.

It is not an unprimeable number, because it can be changed into a prime (21000302923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2038090 + ... + 2048367.

Almost surely, 2^21000302523 is an apocalyptic number.

21000302523 is a deficient number, since it is larger than the sum of its proper divisors (9386599165).

21000302523 is a wasteful number, since it uses less digits than its factorization.

21000302523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4087034 (or 4087031 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 18.

Adding to 21000302523 its reverse (32520300012), we get a palindrome (53520602535).

The spelling of 21000302523 in words is "twenty-one billion, three hundred two thousand, five hundred twenty-three".