2161243445 has 16 divisors (see below), whose sum is σ = 2803779840. Its totient is φ = 1593722304.

The previous prime is 2161243433. The next prime is 2161243451. The reversal of 2161243445 is 5443421612.

It is a cyclic number.

It is not a de Polignac number, because 2161243445 - 2⁴ = 2161243429 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 303917 + ... + 310946.

It is an arithmetic number, because the mean of its divisors is an integer number (175236240).

Almost surely, 2^2161243445 is an apocalyptic number.

It is an amenable number.

2161243445 is a deficient number, since it is larger than the sum of its proper divisors (642536395).

2161243445 is a wasteful number, since it uses less digits than its factorization.

2161243445 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 614924.

The product of its digits is 23040, while the sum is 32.

The square root of 2161243445 is about 46489.1755680825. The cubic root of 2161243445 is about 1292.9088146812.

The spelling of 2161243445 in words is "two billion, one hundred sixty-one million, two hundred forty-three thousand, four hundred forty-five".