21204050989 has 8 divisors (see below), whose sum is σ = 24492379968. Its totient is φ = 18142503360.

The previous prime is 21204050969. The next prime is 21204051047. The reversal of 21204050989 is 98905040212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21204050989 - 2¹¹ = 21204048941 is a prime.

It is a super-2 number, since 2×21204050989² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21204050929) 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, 56695137 + ... + 56695510.

It is an arithmetic number, because the mean of its divisors is an integer number (3061547496).

Almost surely, 2^21204050989 is an apocalyptic number.

It is an amenable number.

21204050989 is a deficient number, since it is larger than the sum of its proper divisors (3288328979).

21204050989 is a wasteful number, since it uses less digits than its factorization.

21204050989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 113390675.

The product of its (nonzero) digits is 51840, while the sum is 40.

The spelling of 21204050989 in words is "twenty-one billion, two hundred four million, fifty thousand, nine hundred eighty-nine".