2161863 has 32 divisors (see below), whose sum is σ = 3628800. Its totient is φ = 1260000.

The previous prime is 2161853. The next prime is 2161871. The reversal of 2161863 is 3681612.

It is not a de Polignac number, because 2161863 - 2¹² = 2157767 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2161813) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8488 + ... + 8738.

It is an arithmetic number, because the mean of its divisors is an integer number (113400).

2^2161863 is an apocalyptic number.

2161863 is a deficient number, since it is larger than the sum of its proper divisors (1466937).

2161863 is a wasteful number, since it uses less digits than its factorization.

2161863 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 300 (or 294 counting only the distinct ones).

The product of its digits is 1728, while the sum is 27.

The square root of 2161863 is about 1470.3275145355. The cubic root of 2161863 is about 129.3032347208.

The spelling of 2161863 in words is "two million, one hundred sixty-one thousand, eight hundred sixty-three".