22455821 has 2 divisors, whose sum is σ = 22455822. Its totient is φ = 22455820.

The previous prime is 22455799. The next prime is 22455863. The reversal of 22455821 is 12855422.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12602500 + 9853321 = 3550^2 + 3139^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-22455821 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22455871) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11227910 + 11227911.

It is an arithmetic number, because the mean of its divisors is an integer number (11227911).

Almost surely, 2^22455821 is an apocalyptic number.

It is an amenable number.

22455821 is a deficient number, since it is larger than the sum of its proper divisors (1).

22455821 is an equidigital number, since it uses as much as digits as its factorization.

22455821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6400, while the sum is 29.

The square root of 22455821 is about 4738.7573265572. The cubic root of 22455821 is about 282.1259141274.

The spelling of 22455821 in words is "twenty-two million, four hundred fifty-five thousand, eight hundred twenty-one".