204123466011661 has 16 divisors (see below), whose sum is σ = 233338095938304. Its totient is φ = 174922372018944.

The previous prime is 204123466011541. The next prime is 204123466011683. The reversal of 204123466011661 is 166110664321402.

It is a cyclic number.

It is not a de Polignac number, because 204123466011661 - 2¹⁹ = 204123465487373 is a prime.

It is a super-2 number, since 2×204123466011661² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (204123466014661) 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 15 ways as a sum of consecutive naturals, for example, 1462792885 + ... + 1462932421.

It is an arithmetic number, because the mean of its divisors is an integer number (14583630996144).

Almost surely, 2^{204123466011661} is an apocalyptic number.

It is an amenable number.

204123466011661 is a deficient number, since it is larger than the sum of its proper divisors (29214629926643).

204123466011661 is a wasteful number, since it uses less digits than its factorization.

204123466011661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 186540.

The product of its (nonzero) digits is 248832, while the sum is 43.

The spelling of 204123466011661 in words is "two hundred four trillion, one hundred twenty-three billion, four hundred sixty-six million, eleven thousand, six hundred sixty-one".