648138005 has 16 divisors (see below), whose sum is σ = 825887664. Its totient is φ = 486604800.

The previous prime is 648137981. The next prime is 648138031. The reversal of 648138005 is 500831846.

It can be written as a sum of positive squares in 8 ways, for example, as 42289009 + 605848996 = 6503^2 + 24614^2 .

It is a de Polignac number, because none of the positive numbers 2^k-648138005 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19205 + ... + 40805.

It is an arithmetic number, because the mean of its divisors is an integer number (51617979).

Almost surely, 2^648138005 is an apocalyptic number.

It is an amenable number.

648138005 is a deficient number, since it is larger than the sum of its proper divisors (177749659).

648138005 is a wasteful number, since it uses less digits than its factorization.

648138005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21976.

The product of its (nonzero) digits is 23040, while the sum is 35.

The square root of 648138005 is about 25458.5546526114. The cubic root of 648138005 is about 865.4111691980.

The spelling of 648138005 in words is "six hundred forty-eight million, one hundred thirty-eight thousand, five".