645548778071 has 16 divisors (see below), whose sum is σ = 677706670080. Its totient is φ = 613733846880.

The previous prime is 645548778059. The next prime is 645548778113. The reversal of 645548778071 is 170877845546.

645548778071 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 645548778071 - 2³⁸ = 370670871127 is a prime.

It is a super-2 number, since 2×645548778071² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 645548777995 and 645548778013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645548778871) 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, 14855786 + ... + 14899176.

It is an arithmetic number, because the mean of its divisors is an integer number (42356666880).

Almost surely, 2^645548778071 is an apocalyptic number.

645548778071 is a deficient number, since it is larger than the sum of its proper divisors (32157892009).

645548778071 is a wasteful number, since it uses less digits than its factorization.

645548778071 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47326.

The product of its (nonzero) digits is 52684800, while the sum is 62.

The spelling of 645548778071 in words is "six hundred forty-five billion, five hundred forty-eight million, seven hundred seventy-eight thousand, seventy-one".