1216800789 has 8 divisors (see below), whose sum is σ = 1717836480. Its totient is φ = 763482816.

The previous prime is 1216800779. The next prime is 1216800803. The reversal of 1216800789 is 9870086121.

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

It is not a de Polignac number, because 1216800789 - 2⁴ = 1216800773 is a prime.

It is a super-2 number, since 2×1216800789² = 2961208320222045042, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1216800789.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216800779) 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, 11929369 + ... + 11929470.

It is an arithmetic number, because the mean of its divisors is an integer number (214729560).

Almost surely, 2^1216800789 is an apocalyptic number.

It is an amenable number.

1216800789 is a deficient number, since it is larger than the sum of its proper divisors (501035691).

1216800789 is a wasteful number, since it uses less digits than its factorization.

1216800789 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23858859.

The product of its (nonzero) digits is 48384, while the sum is 42.

The square root of 1216800789 is about 34882.6717583387. The cubic root of 1216800789 is about 1067.5949092470.

The spelling of 1216800789 in words is "one billion, two hundred sixteen million, eight hundred thousand, seven hundred eighty-nine".