215534464640 has 256 divisors, whose sum is σ = 621053879040. Its totient is φ = 70557696000.

The previous prime is 215534464633. The next prime is 215534464681. The reversal of 215534464640 is 46464435512.

215534464640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a junction number, because it is equal to n+sod(n) for n = 215534464591 and 215534464600.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2713490 + ... + 2791790.

It is an arithmetic number, because the mean of its divisors is an integer number (2425991715).

Almost surely, 2^215534464640 is an apocalyptic number.

215534464640 is a gapful number since it is divisible by the number (20) 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 215534464640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (310526939520).

215534464640 is an abundant number, since it is smaller than the sum of its proper divisors (405519414400).

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

215534464640 is a wasteful number, since it uses less digits than its factorization.

215534464640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78371 (or 78359 counting only the distinct ones).

The product of its (nonzero) digits is 1382400, while the sum is 44.

The spelling of 215534464640 in words is "two hundred fifteen billion, five hundred thirty-four million, four hundred sixty-four thousand, six hundred forty".