22161420 has 144 divisors (see below), whose sum is σ = 72176832. Its totient is φ = 5491200.

The previous prime is 22161407. The next prime is 22161427. The reversal of 22161420 is 2416122.

It is a super-2 number, since 2×22161420² = 982257072832800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 22161393 and 22161402.

It is not an unprimeable number, because it can be changed into a prime (22161427) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 219370 + ... + 219470.

It is an arithmetic number, because the mean of its divisors is an integer number (501228).

Almost surely, 2^22161420 is an apocalyptic number.

22161420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 22161420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36088416).

22161420 is an abundant number, since it is smaller than the sum of its proper divisors (50015412).

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

22161420 is a wasteful number, since it uses less digits than its factorization.

22161420 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 192 (or 187 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 22161420 is about 4707.5917410073. The cubic root of 22161420 is about 280.8875746523.

Adding to 22161420 its reverse (2416122), we get a palindrome (24577542).

The spelling of 22161420 in words is "twenty-two million, one hundred sixty-one thousand, four hundred twenty".