646939226 has 8 divisors (see below), whose sum is σ = 976922100. Its totient is φ = 321298528.

The previous prime is 646939211. The next prime is 646939243. The reversal of 646939226 is 622939646.

It is a Cunningham number, because it is equal to 25435²+1.

It can be written as a sum of positive squares in 2 ways, for example, as 646939225 + 1 = 25435^2 + 1^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1085171 + ... + 1085766.

Almost surely, 2^646939226 is an apocalyptic number.

646939226 is a deficient number, since it is larger than the sum of its proper divisors (329982874).

646939226 is a wasteful number, since it uses less digits than its factorization.

646939226 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2171088.

The product of its digits is 839808, while the sum is 47.

The square root of 646939226 is about 25435.0000196580. Note that the first 4 decimals coincide. The cubic root of 646939226 is about 864.8772926721.

The spelling of 646939226 in words is "six hundred forty-six million, nine hundred thirty-nine thousand, two hundred twenty-six".