215382997440 has 672 divisors, whose sum is σ = 822637984896. Its totient is φ = 51385466880.

The previous prime is 215382997393. The next prime is 215382997447. The reversal of 215382997440 is 44799283512.

215382997440 is a `hidden beast` number, since 215 + 38 + 299 + 74 + 40 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215382997447) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 296262357 + ... + 296263083.

It is an arithmetic number, because the mean of its divisors is an integer number (1224163668).

Almost surely, 2^215382997440 is an apocalyptic number.

215382997440 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 215382997440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (411318992448).

215382997440 is an abundant number, since it is smaller than the sum of its proper divisors (607254987456).

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

215382997440 is a wasteful number, since it uses less digits than its factorization.

215382997440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 997 (or 984 counting only the distinct ones).

The product of its (nonzero) digits is 4354560, while the sum is 54.

The spelling of 215382997440 in words is "two hundred fifteen billion, three hundred eighty-two million, nine hundred ninety-seven thousand, four hundred forty".