646640246 has 16 divisors (see below), whose sum is σ = 1109189376. Its totient is φ = 276965736.

The previous prime is 646640221. The next prime is 646640257. The reversal of 646640246 is 642046646.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12095 + ... + 37941.

It is an arithmetic number, because the mean of its divisors is an integer number (69324336).

Almost surely, 2^646640246 is an apocalyptic number.

646640246 is a deficient number, since it is larger than the sum of its proper divisors (462549130).

646640246 is a wasteful number, since it uses less digits than its factorization.

646640246 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27643.

The product of its (nonzero) digits is 165888, while the sum is 38.

The square root of 646640246 is about 25429.1220060780. The cubic root of 646640246 is about 864.7440391160.

The spelling of 646640246 in words is "six hundred forty-six million, six hundred forty thousand, two hundred forty-six".