645646505652 has 36 divisors (see below), whose sum is σ = 1632093014916. Its totient is φ = 215209946880.

The previous prime is 645646505639. The next prime is 645646505657. The reversal of 645646505652 is 256505646546.

It is a happy number.

645646505652 is a `hidden beast` number, since 6 + 45 + 6 + 46 + 505 + 6 + 52 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 342358392996 + 303288112656 = 585114^2 + 550716^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645646505657) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1326252 + ... + 1746492.

It is an arithmetic number, because the mean of its divisors is an integer number (45335917081).

Almost surely, 2^645646505652 is an apocalyptic number.

It is an amenable number.

645646505652 is an abundant number, since it is smaller than the sum of its proper divisors (986446509264).

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

645646505652 is a wasteful number, since it uses less digits than its factorization.

645646505652 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 462928 (or 462923 counting only the distinct ones).

The product of its (nonzero) digits is 25920000, while the sum is 54.

The spelling of 645646505652 in words is "six hundred forty-five billion, six hundred forty-six million, five hundred five thousand, six hundred fifty-two".