223672217921 has 2 divisors, whose sum is σ = 223672217922. Its totient is φ = 223672217920.

The previous prime is 223672217869. The next prime is 223672218023. The reversal of 223672217921 is 129712276322.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 185437890625 + 38234327296 = 430625^2 + 195536^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-223672217921 is a prime.

It is a super-2 number, since 2×223672217921² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (223602217921) 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 as a sum of consecutive naturals, namely, 111836108960 + 111836108961.

It is an arithmetic number, because the mean of its divisors is an integer number (111836108961).

Almost surely, 2^223672217921 is an apocalyptic number.

It is an amenable number.

223672217921 is a deficient number, since it is larger than the sum of its proper divisors (1).

223672217921 is an equidigital number, since it uses as much as digits as its factorization.

223672217921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 254016, while the sum is 44.

The spelling of 223672217921 in words is "two hundred twenty-three billion, six hundred seventy-two million, two hundred seventeen thousand, nine hundred twenty-one".