646256026 has 8 divisors (see below), whose sum is σ = 1043952084. Its totient is φ = 298272000.

The previous prime is 646255999. The next prime is 646256057. The reversal of 646256026 is 620652646.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 625050001 + 21206025 = 25001^2 + 4605^2 .

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

It is a super-2 number, since 2×646256026² = 835293702282625352, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12427975 + ... + 12428026.

Almost surely, 2^646256026 is an apocalyptic number.

646256026 is a deficient number, since it is larger than the sum of its proper divisors (397696058).

646256026 is a wasteful number, since it uses less digits than its factorization.

646256026 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24856016.

The product of its (nonzero) digits is 103680, while the sum is 37.

The square root of 646256026 is about 25421.5661594639. The cubic root of 646256026 is about 864.5727342913.

The spelling of 646256026 in words is "six hundred forty-six million, two hundred fifty-six thousand, twenty-six".