648991694 has 24 divisors (see below), whose sum is σ = 1113680568. Its totient is φ = 281911680.

The previous prime is 648991669. The next prime is 648991697. The reversal of 648991694 is 496199846.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (648991697) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 35672 + ... + 50699.

It is an arithmetic number, because the mean of its divisors is an integer number (46403357).

Almost surely, 2^648991694 is an apocalyptic number.

648991694 is a deficient number, since it is larger than the sum of its proper divisors (464688874).

648991694 is a wasteful number, since it uses less digits than its factorization.

648991694 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86420 (or 86403 counting only the distinct ones).

The product of its digits is 3359232, while the sum is 56.

The square root of 648991694 is about 25475.3153856827. The cubic root of 648991694 is about 865.7909586167.

The spelling of 648991694 in words is "six hundred forty-eight million, nine hundred ninety-one thousand, six hundred ninety-four".