187216969 has 4 divisors (see below), whose sum is σ = 191570896. Its totient is φ = 182863044.

The previous prime is 187216963. The next prime is 187216973. The reversal of 187216969 is 969612781.

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, and also an emirpimes, since its reverse is a distinct semiprime: 969612781 = 521 ⋅1861061.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-187216969 is a prime.

It is a super-2 number, since 2×187216969² = 70100386963093922, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (187216963) 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, 2176899 + ... + 2176984.

It is an arithmetic number, because the mean of its divisors is an integer number (47892724).

Almost surely, 2^187216969 is an apocalyptic number.

It is an amenable number.

187216969 is a deficient number, since it is larger than the sum of its proper divisors (4353927).

187216969 is an equidigital number, since it uses as much as digits as its factorization.

187216969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4353926.

The product of its digits is 326592, while the sum is 49.

The square root of 187216969 is about 13682.7252037012. The cubic root of 187216969 is about 572.0689854773.

It can be divided in two parts, 187 and 216969, that added together give a square (217156 = 466²).

The spelling of 187216969 in words is "one hundred eighty-seven million, two hundred sixteen thousand, nine hundred sixty-nine".