645261304416 has 48 divisors (see below), whose sum is σ = 1694339564400. Its totient is φ = 215019972608.

The previous prime is 645261304411. The next prime is 645261304417. The reversal of 645261304416 is 614403162546.

It is a tau number, because it is divible by the number of its divisors (48).

It is a super-2 number, since 2×645261304416² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645261304411) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 739221 + ... + 1355348.

It is an arithmetic number, because the mean of its divisors is an integer number (35298740925).

Almost surely, 2^645261304416 is an apocalyptic number.

It is an amenable number.

645261304416 is an abundant number, since it is smaller than the sum of its proper divisors (1049078259984).

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

645261304416 is a wasteful number, since it uses less digits than its factorization.

645261304416 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2097791 (or 2097783 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 42.

The spelling of 645261304416 in words is "six hundred forty-five billion, two hundred sixty-one million, three hundred four thousand, four hundred sixteen".