172927661 has 2 divisors, whose sum is σ = 172927662. Its totient is φ = 172927660.

The previous prime is 172927637. The next prime is 172927669. The reversal of 172927661 is 166729271.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 103938025 + 68989636 = 10195^2 + 8306^2 .

It is an emirp because it is prime and its reverse (166729271) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 172927661 - 2⁶ = 172927597 is a prime.

It is a Chen prime.

It is equal to p_9657590 and since 172927661 and 9657590 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (172927669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86463830 + 86463831.

It is an arithmetic number, because the mean of its divisors is an integer number (86463831).

Almost surely, 2^172927661 is an apocalyptic number.

It is an amenable number.

172927661 is a deficient number, since it is larger than the sum of its proper divisors (1).

172927661 is an equidigital number, since it uses as much as digits as its factorization.

172927661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 63504, while the sum is 41.

The square root of 172927661 is about 13150.1962342773. The cubic root of 172927661 is about 557.1277905916.

The spelling of 172927661 in words is "one hundred seventy-two million, nine hundred twenty-seven thousand, six hundred sixty-one".