649488688 has 40 divisors (see below), whose sum is σ = 1317344256. Its totient is φ = 309825600.

The previous prime is 649488683. The next prime is 649488731. The reversal of 649488688 is 886884946.

It is a super-2 number, since 2×649488688² = 843671111679922688, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (649488683) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 25995 + ... + 44437.

Almost surely, 2^649488688 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 649488688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (658672128).

649488688 is an abundant number, since it is smaller than the sum of its proper divisors (667855568).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

649488688 is a wasteful number, since it uses less digits than its factorization.

649488688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18553 (or 18547 counting only the distinct ones).

The product of its digits is 21233664, while the sum is 61.

The square root of 649488688 is about 25485.0679418361. The cubic root of 649488688 is about 866.0119080904.

The spelling of 649488688 in words is "six hundred forty-nine million, four hundred eighty-eight thousand, six hundred eighty-eight".