172403567056661 has 2 divisors, whose sum is σ = 172403567056662. Its totient is φ = 172403567056660.

The previous prime is 172403567056639. The next prime is 172403567056733. The reversal of 172403567056661 is 166650765304271.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 168930301187761 + 3473265868900 = 12997319^2 + 1863670^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-172403567056661 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 172403567056661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (172403567053661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 86201783528330 + 86201783528331.

It is an arithmetic number, because the mean of its divisors is an integer number (86201783528331).

Almost surely, 2^{172403567056661} is an apocalyptic number.

It is an amenable number.

172403567056661 is a deficient number, since it is larger than the sum of its proper divisors (1).

172403567056661 is an equidigital number, since it uses as much as digits as its factorization.

172403567056661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 38102400, while the sum is 59.

The spelling of 172403567056661 in words is "one hundred seventy-two trillion, four hundred three billion, five hundred sixty-seven million, fifty-six thousand, six hundred sixty-one".