2143454611661 has 16 divisors (see below), whose sum is σ = 2339786260800. Its totient is φ = 1947368755200.

The previous prime is 2143454611621. The next prime is 2143454611663. The reversal of 2143454611661 is 1661164543412.

It is not a de Polignac number, because 2143454611661 - 2²⁶ = 2143387502797 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2143454611663) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 152216141 + ... + 152230221.

It is an arithmetic number, because the mean of its divisors is an integer number (146236641300).

Almost surely, 2^{2143454611661} is an apocalyptic number.

It is an amenable number.

2143454611661 is a deficient number, since it is larger than the sum of its proper divisors (196331649139).

2143454611661 is a wasteful number, since it uses less digits than its factorization.

2143454611661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21820.

The product of its digits is 414720, while the sum is 44.

The spelling of 2143454611661 in words is "two trillion, one hundred forty-three billion, four hundred fifty-four million, six hundred eleven thousand, six hundred sixty-one".