20989429678 has 24 divisors (see below), whose sum is σ = 38102517936. Its totient is φ = 8465423040.

The previous prime is 20989429633. The next prime is 20989429693. The reversal of 20989429678 is 87692498902.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2230363 + ... + 2239753.

It is an arithmetic number, because the mean of its divisors is an integer number (1587604914).

Almost surely, 2^20989429678 is an apocalyptic number.

20989429678 is a deficient number, since it is larger than the sum of its proper divisors (17113088258).

20989429678 is an frugal number, since it uses more digits than its factorization.

20989429678 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18808 (or 9417 counting only the distinct ones).

The product of its (nonzero) digits is 31352832, while the sum is 64.

The spelling of 20989429678 in words is "twenty billion, nine hundred eighty-nine million, four hundred twenty-nine thousand, six hundred seventy-eight".