2161236 has 48 divisors (see below), whose sum is σ = 6289920. Its totient is φ = 561120.

The previous prime is 2161213. The next prime is 2161253. The reversal of 2161236 is 6321612.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a nude number because it is divisible by every one of its digits.

It is an Ulam number.

It is an alternating number because its digits alternate between even and odd.

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, 246 + ... + 2093.

It is an arithmetic number, because the mean of its divisors is an integer number (131040).

2^2161236 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2161236, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3144960).

2161236 is an abundant number, since it is smaller than the sum of its proper divisors (4128684).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2161236 is a wasteful number, since it uses less digits than its factorization.

2161236 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2364 (or 2362 counting only the distinct ones).

The product of its digits is 432, while the sum is 21.

The square root of 2161236 is about 1470.1142812720. The cubic root of 2161236 is about 129.2907330086.

Adding to 2161236 its reverse (6321612), we get a palindrome (8482848).

It can be divided in two parts, 21 and 61236, that multiplied together give a square (1285956 = 1134²).

The spelling of 2161236 in words is "two million, one hundred sixty-one thousand, two hundred thirty-six".