649386864 has 240 divisors, whose sum is σ = 2242356480. Its totient is φ = 171279360.

The previous prime is 649386851. The next prime is 649386869. The reversal of 649386864 is 468683946.

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 649386864.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (649386869) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 784819 + ... + 785645.

It is an arithmetic number, because the mean of its divisors is an integer number (9343152).

Almost surely, 2^649386864 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 649386864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1121178240).

649386864 is an abundant number, since it is smaller than the sum of its proper divisors (1592969616).

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

649386864 is a wasteful number, since it uses less digits than its factorization.

649386864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 908 (or 899 counting only the distinct ones).

The product of its digits is 5971968, while the sum is 54.

The square root of 649386864 is about 25483.0701447059. The cubic root of 649386864 is about 865.9666492036.

The spelling of 649386864 in words is "six hundred forty-nine million, three hundred eighty-six thousand, eight hundred sixty-four".