649687500 has 384 divisors, whose sum is σ = 2624993280. Its totient is φ = 135000000.

The previous prime is 649687469. The next prime is 649687523. The reversal of 649687500 is 5786946.

649687500 is a `hidden beast` number, since 64 + 9 + 6 + 87 + 500 = 666.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 59062495 + ... + 59062505.

It is an arithmetic number, because the mean of its divisors is an integer number (6835920).

Almost surely, 2^649687500 is an apocalyptic number.

649687500 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 649687500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1312496640).

649687500 is an abundant number, since it is smaller than the sum of its proper divisors (1975305780).

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

649687500 is an equidigital number, since it uses as much as digits as its factorization.

649687500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66 (or 28 counting only the distinct ones).

The product of its (nonzero) digits is 362880, while the sum is 45.

The square root of 649687500 is about 25488.9682019496. The cubic root of 649687500 is about 866.1002627187.

The spelling of 649687500 in words is "six hundred forty-nine million, six hundred eighty-seven thousand, five hundred".