190156605555661 has 2 divisors, whose sum is σ = 190156605555662. Its totient is φ = 190156605555660.

The previous prime is 190156605555643. The next prime is 190156605555781. The reversal of 190156605555661 is 166555506651091.

190156605555661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 156250150000036 + 33906455555625 = 12500006^2 + 5822925^2 .

It is a cyclic number.

It is not a de Polignac number, because 190156605555661 - 2³¹ = 190154458072013 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 190156605555661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (190156605555061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 95078302777830 + 95078302777831.

It is an arithmetic number, because the mean of its divisors is an integer number (95078302777831).

Almost surely, 2^{190156605555661} is an apocalyptic number.

It is an amenable number.

190156605555661 is a deficient number, since it is larger than the sum of its proper divisors (1).

190156605555661 is an equidigital number, since it uses as much as digits as its factorization.

190156605555661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36450000, while the sum is 61.

The spelling of 190156605555661 in words is "one hundred ninety trillion, one hundred fifty-six billion, six hundred five million, five hundred fifty-five thousand, six hundred sixty-one".