2117929 has 4 divisors (see below), whose sum is σ = 2310480. Its totient is φ = 1925380.

The previous prime is 2117903. The next prime is 2117953. The reversal of 2117929 is 9297112.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2117929 is a prime.

It is a Smith number, since the sum of its digits (31) 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 a self number, because there is not a number n which added to its sum of digits gives 2117929.

It is not an unprimeable number, because it can be changed into a prime (2117429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 96259 + ... + 96280.

It is an arithmetic number, because the mean of its divisors is an integer number (577620).

2^2117929 is an apocalyptic number.

It is an amenable number.

2117929 is a deficient number, since it is larger than the sum of its proper divisors (192551).

2117929 is a wasteful number, since it uses less digits than its factorization.

2117929 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 192550.

The product of its digits is 2268, while the sum is 31.

The square root of 2117929 is about 1455.3106197647. The cubic root of 2117929 is about 128.4213208190.

It can be divided in two parts, 211792 and 9, that multiplied together give a triangular number (1906128 = T₁₉₅₂).

The spelling of 2117929 in words is "two million, one hundred seventeen thousand, nine hundred twenty-nine".