640464246 has 40 divisors (see below), whose sum is σ = 1484611920. Its totient is φ = 206124912.

The previous prime is 640464241. The next prime is 640464263. The reversal of 640464246 is 642464046.

It is a happy number.

640464246 is a `hidden beast` number, since 6 + 4 + 0 + 4 + 642 + 4 + 6 = 666.

It is a self number, because there is not a number n which added to its sum of digits gives 640464246.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (640464241) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 63466 + ... + 72861.

It is an arithmetic number, because the mean of its divisors is an integer number (37115298).

Almost surely, 2^640464246 is an apocalyptic number.

640464246 is an abundant number, since it is smaller than the sum of its proper divisors (844147674).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

640464246 is a wasteful number, since it uses less digits than its factorization.

640464246 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136370 (or 136361 counting only the distinct ones).

The product of its (nonzero) digits is 110592, while the sum is 36.

The square root of 640464246 is about 25307.3950852315. The cubic root of 640464246 is about 861.9821980845.

The spelling of 640464246 in words is "six hundred forty million, four hundred sixty-four thousand, two hundred forty-six".