188213969 has 4 divisors (see below), whose sum is σ = 189477300. Its totient is φ = 186950640.

The previous prime is 188213959. The next prime is 188214017. The reversal of 188213969 is 969312881.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 969312881 = 199 ⋅4870919.

It can be written as a sum of positive squares in 2 ways, for example, as 81360400 + 106853569 = 9020^2 + 10337^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-188213969 is a prime.

It is a super-2 number, since 2×188213969² = 70848996253465922, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (188213939) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 631442 + ... + 631739.

It is an arithmetic number, because the mean of its divisors is an integer number (47369325).

Almost surely, 2^188213969 is an apocalyptic number.

It is an amenable number.

188213969 is a deficient number, since it is larger than the sum of its proper divisors (1263331).

188213969 is a wasteful number, since it uses less digits than its factorization.

188213969 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1263330.

The product of its digits is 186624, while the sum is 47.

The square root of 188213969 is about 13719.1096285437. The cubic root of 188213969 is about 573.0826815460.

It can be divided in two parts, 1882 and 13969, that added together give a palindrome (15851).

The spelling of 188213969 in words is "one hundred eighty-eight million, two hundred thirteen thousand, nine hundred sixty-nine".