22161921 has 8 divisors (see below), whose sum is σ = 29704704. Its totient is φ = 14696880.

The previous prime is 22161917. The next prime is 22161929. The reversal of 22161921 is 12916122.

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

It is not a de Polignac number, because 22161921 - 2² = 22161917 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 22161891 and 22161900.

It is not an unprimeable number, because it can be changed into a prime (22161929) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18766 + ... + 19911.

It is an arithmetic number, because the mean of its divisors is an integer number (3713088).

Almost surely, 2^22161921 is an apocalyptic number.

It is an amenable number.

22161921 is a deficient number, since it is larger than the sum of its proper divisors (7542783).

22161921 is a wasteful number, since it uses less digits than its factorization.

22161921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38871.

The product of its digits is 432, while the sum is 24.

The square root of 22161921 is about 4707.6449526276. The cubic root of 22161921 is about 280.8896912979.

The spelling of 22161921 in words is "twenty-two million, one hundred sixty-one thousand, nine hundred twenty-one".