215638698240 has 648 divisors, whose sum is σ = 895967025408. Its totient is φ = 47695011840.

The previous prime is 215638698161. The next prime is 215638698241. The reversal of 215638698240 is 42896836512.

215638698240 is a `hidden beast` number, since 2 + 15 + 6 + 386 + 9 + 8 + 240 = 666.

215638698240 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (215638698241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 17492719 + ... + 17505041.

Almost surely, 2^215638698240 is an apocalyptic number.

215638698240 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 215638698240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (447983512704).

215638698240 is an abundant number, since it is smaller than the sum of its proper divisors (680328327168).

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

215638698240 is a wasteful number, since it uses less digits than its factorization.

215638698240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12395 (or 12371 counting only the distinct ones).

The product of its (nonzero) digits is 4976640, while the sum is 54.

It can be divided in two parts, 2156386 and 98240, that added together give a triangular number (2254626 = T₂₁₂₃).

The spelling of 215638698240 in words is "two hundred fifteen billion, six hundred thirty-eight million, six hundred ninety-eight thousand, two hundred forty".