2161906815 has 8 divisors (see below), whose sum is σ = 3459050928. Its totient is φ = 1153016960.

The previous prime is 2161906793. The next prime is 2161906823. The reversal of 2161906815 is 5186091612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 2161906815 - 2⁷ = 2161906687 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 72063546 + ... + 72063575.

It is an arithmetic number, because the mean of its divisors is an integer number (432381366).

Almost surely, 2^2161906815 is an apocalyptic number.

2161906815 is a deficient number, since it is larger than the sum of its proper divisors (1297144113).

2161906815 is a wasteful number, since it uses less digits than its factorization.

2161906815 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144127129.

The product of its (nonzero) digits is 25920, while the sum is 39.

The square root of 2161906815 is about 46496.3096922756. The cubic root of 2161906815 is about 1293.0410825485.

The spelling of 2161906815 in words is "two billion, one hundred sixty-one million, nine hundred six thousand, eight hundred fifteen".