645022222 has 16 divisors (see below), whose sum is σ = 1096799760. Its totient is φ = 282033792.

The previous prime is 645022207. The next prime is 645022223. The reversal of 645022222 is 222220546.

It is a happy number.

645022222 is a modest number, since divided by 22222 gives 6450 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645022223) 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, 652363 + ... + 653350.

It is an arithmetic number, because the mean of its divisors is an integer number (68549985).

Almost surely, 2^645022222 is an apocalyptic number.

645022222 is a deficient number, since it is larger than the sum of its proper divisors (451777538).

645022222 is a wasteful number, since it uses less digits than its factorization.

645022222 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1305747.

The product of its (nonzero) digits is 3840, while the sum is 25.

The square root of 645022222 is about 25397.2876898302. The cubic root of 645022222 is about 864.0221821794.

Adding to 645022222 its reverse (222220546), we get a palindrome (867242768).

The spelling of 645022222 in words is "six hundred forty-five million, twenty-two thousand, two hundred twenty-two".