22161506 has 8 divisors (see below), whose sum is σ = 35197740. Its totient is φ = 10428928.

The previous prime is 22161499. The next prime is 22161509. The reversal of 22161506 is 60516122.

It can be written as a sum of positive squares in 2 ways, for example, as 22005481 + 156025 = 4691^2 + 395^2 .

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

It is a super-2 number, since 2×22161506² = 982264696376072, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (22161509) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 325871 + ... + 325938.

Almost surely, 2^22161506 is an apocalyptic number.

22161506 is a deficient number, since it is larger than the sum of its proper divisors (13036234).

22161506 is a wasteful number, since it uses less digits than its factorization.

22161506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 651828.

The product of its (nonzero) digits is 720, while the sum is 23.

The square root of 22161506 is about 4707.6008751805. The cubic root of 22161506 is about 280.8879379909.

Adding to 22161506 its reverse (60516122), we get a palindrome (82677628).

The spelling of 22161506 in words is "twenty-two million, one hundred sixty-one thousand, five hundred six".