21017950716 has 24 divisors (see below), whose sum is σ = 56047868800. Its totient is φ = 6005128752.

The previous prime is 21017950703. The next prime is 21017950717. The reversal of 21017950716 is 61705971012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21017950717) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 125106766 + ... + 125106933.

Almost surely, 2^21017950716 is an apocalyptic number.

It is an amenable number.

21017950716 is an abundant number, since it is smaller than the sum of its proper divisors (35029918084).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21017950716 is a wasteful number, since it uses less digits than its factorization.

21017950716 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 250213713 (or 250213711 counting only the distinct ones).

The product of its (nonzero) digits is 26460, while the sum is 39.

The spelling of 21017950716 in words is "twenty-one billion, seventeen million, nine hundred fifty thousand, seven hundred sixteen".