21436516688 has 10 divisors (see below), whose sum is σ = 41533251114. Its totient is φ = 10718258336.

The previous prime is 21436516613. The next prime is 21436516697. The reversal of 21436516688 is 88661563412.

It can be written as a sum of positive squares in only one way, i.e., 20986737424 + 449779264 = 144868^2 + 21208^2 .

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 as a sum of consecutive naturals, namely, 669891131 + ... + 669891162.

Almost surely, 2^21436516688 is an apocalyptic number.

It is an amenable number.

21436516688 is a deficient number, since it is larger than the sum of its proper divisors (20096734426).

21436516688 is a wasteful number, since it uses less digits than its factorization.

21436516688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1339782301 (or 1339782295 counting only the distinct ones).

The product of its digits is 1658880, while the sum is 50.

The spelling of 21436516688 in words is "twenty-one billion, four hundred thirty-six million, five hundred sixteen thousand, six hundred eighty-eight".