648215136 has 168 divisors, whose sum is σ = 1967714784. Its totient is φ = 209952000.

The previous prime is 648215131. The next prime is 648215149. The reversal of 648215136 is 631512846.

It is a happy number.

648215136 is a `hidden beast` number, since 64 + 82 + 1 + 513 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 648215136.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (648215131) by changing a digit.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 862761 + ... + 863511.

It is an arithmetic number, because the mean of its divisors is an integer number (11712588).

Almost surely, 2^648215136 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 648215136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (983857392).

648215136 is an abundant number, since it is smaller than the sum of its proper divisors (1319499648).

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

648215136 is an equidigital number, since it uses as much as digits as its factorization.

648215136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 816 (or 793 counting only the distinct ones).

The product of its digits is 34560, while the sum is 36.

The square root of 648215136 is about 25460.0694421677. The cubic root of 648215136 is about 865.4454969598.

The spelling of 648215136 in words is "six hundred forty-eight million, two hundred fifteen thousand, one hundred thirty-six".