217031129899 has 4 divisors (see below), whose sum is σ = 217038488920. Its totient is φ = 217023770880.

The previous prime is 217031129849. The next prime is 217031129929. The reversal of 217031129899 is 998921130712.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 217031129899 - 2¹¹ = 217031127851 is a prime.

It is a super-2 number, since 2×217031129899² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (217031129839) 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, 3635094 + ... + 3694315.

It is an arithmetic number, because the mean of its divisors is an integer number (54259622230).

Almost surely, 2^217031129899 is an apocalyptic number.

217031129899 is a deficient number, since it is larger than the sum of its proper divisors (7359021).

217031129899 is an equidigital number, since it uses as much as digits as its factorization.

217031129899 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7359020.

The product of its (nonzero) digits is 489888, while the sum is 52.

The spelling of 217031129899 in words is "two hundred seventeen billion, thirty-one million, one hundred twenty-nine thousand, eight hundred ninety-nine".