22154809 has 2 divisors, whose sum is σ = 22154810. Its totient is φ = 22154808.

The previous prime is 22154777. The next prime is 22154833. The reversal of 22154809 is 90845122.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16646400 + 5508409 = 4080^2 + 2347^2 .

It is a cyclic number.

It is not a de Polignac number, because 22154809 - 2⁵ = 22154777 is a prime.

It is equal to p_1398370 and since 22154809 and 1398370 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (22154879) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11077404 + 11077405.

It is an arithmetic number, because the mean of its divisors is an integer number (11077405).

Almost surely, 2^22154809 is an apocalyptic number.

It is an amenable number.

22154809 is a deficient number, since it is larger than the sum of its proper divisors (1).

22154809 is an equidigital number, since it uses as much as digits as its factorization.

22154809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5760, while the sum is 31.

The square root of 22154809 is about 4706.8895249411. The cubic root of 22154809 is about 280.8596412371.

The spelling of 22154809 in words is "twenty-two million, one hundred fifty-four thousand, eight hundred nine".