645505613743 has 16 divisors (see below), whose sum is σ = 670492579680. Its totient is φ = 620703893376.

The previous prime is 645505613699. The next prime is 645505613807. The reversal of 645505613743 is 347316505546.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-645505613743 is a prime.

It is a super-2 number, since 2×645505613743² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645505643743) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10983705 + ... + 11042317.

It is an arithmetic number, because the mean of its divisors is an integer number (41905786230).

Almost surely, 2^645505613743 is an apocalyptic number.

645505613743 is a deficient number, since it is larger than the sum of its proper divisors (24986965937).

645505613743 is a wasteful number, since it uses less digits than its factorization.

645505613743 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60186.

The product of its (nonzero) digits is 4536000, while the sum is 49.

The spelling of 645505613743 in words is "six hundred forty-five billion, five hundred five million, six hundred thirteen thousand, seven hundred forty-three".