29991678789 has 8 divisors (see below), whose sum is σ = 39991440832. Its totient is φ = 19993184640.

The previous prime is 29991678679. The next prime is 29991678833. The reversal of 29991678789 is 98787619992.

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

It is a de Polignac number, because none of the positive numbers 2^k-29991678789 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 29991678789.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (29991678089) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 260332 + ... + 357429.

It is an arithmetic number, because the mean of its divisors is an integer number (4998930104).

Almost surely, 2^29991678789 is an apocalyptic number.

It is an amenable number.

29991678789 is a deficient number, since it is larger than the sum of its proper divisors (9999762043).

29991678789 is a wasteful number, since it uses less digits than its factorization.

29991678789 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 633947.

The product of its digits is 246903552, while the sum is 75.

The spelling of 29991678789 in words is "twenty-nine billion, nine hundred ninety-one million, six hundred seventy-eight thousand, seven hundred eighty-nine".