648781539 has 16 divisors (see below), whose sum is σ = 1031603712. Its totient is φ = 354613248.

The previous prime is 648781531. The next prime is 648781559. The reversal of 648781539 is 935187846.

It is not a de Polignac number, because 648781539 - 2³ = 648781531 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 648781491 and 648781500.

It is not an unprimeable number, because it can be changed into a prime (648781531) 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, 671134 + ... + 672099.

It is an arithmetic number, because the mean of its divisors is an integer number (64475232).

Almost surely, 2^648781539 is an apocalyptic number.

648781539 is a gapful number since it is divisible by the number (69) formed by its first and last digit.

648781539 is a deficient number, since it is larger than the sum of its proper divisors (382822173).

648781539 is a wasteful number, since it uses less digits than its factorization.

648781539 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1343266.

The product of its digits is 1451520, while the sum is 51.

The square root of 648781539 is about 25471.1903726544. The cubic root of 648781539 is about 865.6974957143.

The spelling of 648781539 in words is "six hundred forty-eight million, seven hundred eighty-one thousand, five hundred thirty-nine".