1661057253085 has 24 divisors (see below), whose sum is σ = 2072278671840. Its totient is φ = 1278089759520.

The previous prime is 1661057253083. The next prime is 1661057253139. The reversal of 1661057253085 is 5803527501661.

It is not a de Polignac number, because 1661057253085 - 2¹ = 1661057253083 is a prime.

It is a super-2 number, since 2×1661057253085² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1661057253083) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 277195 + ... + 1843624.

It is an arithmetic number, because the mean of its divisors is an integer number (86344944660).

Almost surely, 2^{1661057253085} is an apocalyptic number.

It is an amenable number.

1661057253085 is a deficient number, since it is larger than the sum of its proper divisors (411221418755).

1661057253085 is a wasteful number, since it uses less digits than its factorization.

1661057253085 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2121049 (or 2121018 counting only the distinct ones).

The product of its (nonzero) digits is 1512000, while the sum is 49.

The spelling of 1661057253085 in words is "one trillion, six hundred sixty-one billion, fifty-seven million, two hundred fifty-three thousand, eighty-five".