215487381780 has 384 divisors, whose sum is σ = 792396380160. Its totient is φ = 48022087680.

The previous prime is 215487381779. The next prime is 215487381787. The reversal of 215487381780 is 87183784512.

215487381780 is a `hidden beast` number, since 2 + 1 + 5 + 487 + 3 + 81 + 7 + 80 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215487381787) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 4317327 + ... + 4366953.

It is an arithmetic number, because the mean of its divisors is an integer number (2063532240).

Almost surely, 2^215487381780 is an apocalyptic number.

215487381780 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 215487381780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (396198190080).

215487381780 is an abundant number, since it is smaller than the sum of its proper divisors (576908998380).

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

215487381780 is a wasteful number, since it uses less digits than its factorization.

215487381780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49716 (or 49708 counting only the distinct ones).

The product of its (nonzero) digits is 3010560, while the sum is 54.

The spelling of 215487381780 in words is "two hundred fifteen billion, four hundred eighty-seven million, three hundred eighty-one thousand, seven hundred eighty".