648723802005 has 18 divisors (see below), whose sum is σ = 1124463955446. Its totient is φ = 345983146128.

The previous prime is 648723801949. The next prime is 648723802007. The reversal of 648723802005 is 500208327846.

648723802005 is a `hidden beast` number, since 64 + 8 + 7 + 2 + 380 + 200 + 5 = 666.

It can be written as a sum of positive squares in only one way, i.e., 518979041604 + 129744760401 = 720402^2 + 360201^2 .

It is not a de Polignac number, because 648723802005 - 2⁶ = 648723801941 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (648723802007) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 5342982 + ... + 5463048.

It is an arithmetic number, because the mean of its divisors is an integer number (62470219747).

Almost surely, 2^648723802005 is an apocalyptic number.

It is an amenable number.

648723802005 is a deficient number, since it is larger than the sum of its proper divisors (475740153441).

648723802005 is an frugal number, since it uses more digits than its factorization.

648723802005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 240145 (or 120075 counting only the distinct ones).

The product of its (nonzero) digits is 645120, while the sum is 45.

Multiplying 648723802005 by its sum of digits (45), we get a square (29192571090225 = 5403015²).

648723802005 divided by its sum of digits (45) gives a square (14416084489 = 120067²).

The spelling of 648723802005 in words is "six hundred forty-eight billion, seven hundred twenty-three million, eight hundred two thousand, five".