1654789940161 has 4 divisors (see below), whose sum is σ = 1654857725524. Its totient is φ = 1654722154800.

The previous prime is 1654789940149. The next prime is 1654789940171. The reversal of 1654789940161 is 1610499874561.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 648941413761 + 1005848526400 = 805569^2 + 1002920^2 .

It is a cyclic number.

It is not a de Polignac number, because 1654789940161 - 2⁷ = 1654789940033 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1654789940161.

It is not an unprimeable number, because it can be changed into a prime (1654789940171) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33856050 + ... + 33904891.

It is an arithmetic number, because the mean of its divisors is an integer number (413714431381).

Almost surely, 2^{1654789940161} is an apocalyptic number.

It is an amenable number.

1654789940161 is a deficient number, since it is larger than the sum of its proper divisors (67785363).

1654789940161 is an equidigital number, since it uses as much as digits as its factorization.

1654789940161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67785362.

The product of its (nonzero) digits is 13063680, while the sum is 61.

The spelling of 1654789940161 in words is "one trillion, six hundred fifty-four billion, seven hundred eighty-nine million, nine hundred forty thousand, one hundred sixty-one".