22161996 has 36 divisors (see below), whose sum is σ = 56703192. Its totient is φ = 7297344.

The previous prime is 22161991. The next prime is 22162009. The reversal of 22161996 is 69916122.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

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

It is a zygodrome in base 3.

It is a self number, because there is not a number n which added to its sum of digits gives 22161996.

It is not an unprimeable number, because it can be changed into a prime (22161991) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 721 + ... + 6696.

Almost surely, 2^22161996 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 22161996, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28351596).

22161996 is an abundant number, since it is smaller than the sum of its proper divisors (34541196).

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

22161996 is a wasteful number, since it uses less digits than its factorization.

22161996 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7510 (or 7505 counting only the distinct ones).

The product of its digits is 11664, while the sum is 36.

The square root of 22161996 is about 4707.6529183873. The cubic root of 22161996 is about 280.8900081582.

The spelling of 22161996 in words is "twenty-two million, one hundred sixty-one thousand, nine hundred ninety-six".