238721165281 has 9 divisors (see below), whose sum is σ = 246685908819. Its totient is φ = 231005824800.

The previous prime is 238721165273. The next prime is 238721165299. The reversal of 238721165281 is 182561127832.

It is a happy number.

The square root of 238721165281 is 488591.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 151625350881 + 87095814400 = 389391^2 + 295120^2 .

It is not a de Polignac number, because 238721165281 - 2³ = 238721165273 is a prime.

It is a super-2 number, since 2×238721165281² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (238721165261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 15138441 + ... + 15154201.

Almost surely, 2^238721165281 is an apocalyptic number.

238721165281 is the 488591-st square number.

238721165281 is the 244296-th centered octagonal number.

It is an amenable number.

238721165281 is a deficient number, since it is larger than the sum of its proper divisors (7964743538).

238721165281 is an frugal number, since it uses more digits than its factorization.

238721165281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31584 (or 15792 counting only the distinct ones).

The product of its digits is 322560, while the sum is 46.

The spelling of 238721165281 in words is "two hundred thirty-eight billion, seven hundred twenty-one million, one hundred sixty-five thousand, two hundred eighty-one".