216712091929 has 4 divisors (see below), whose sum is σ = 217483309620. Its totient is φ = 215940874240.

The previous prime is 216712091903. The next prime is 216712091971. The reversal of 216712091929 is 929190217612.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 71609760000 + 145102331929 = 267600^2 + 380923^2 .

It is a cyclic number.

It is not a de Polignac number, because 216712091929 - 2⁹ = 216712091417 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (216712091329) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 385608424 + ... + 385608985.

It is an arithmetic number, because the mean of its divisors is an integer number (54370827405).

Almost surely, 2^216712091929 is an apocalyptic number.

It is an amenable number.

216712091929 is a deficient number, since it is larger than the sum of its proper divisors (771217691).

216712091929 is an equidigital number, since it uses as much as digits as its factorization.

216712091929 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 771217690.

The product of its (nonzero) digits is 244944, while the sum is 49.

The spelling of 216712091929 in words is "two hundred sixteen billion, seven hundred twelve million, ninety-one thousand, nine hundred twenty-nine".