215618140 has 96 divisors (see below), whose sum is σ = 498161664. Its totient is φ = 78074880.

The previous prime is 215618119. The next prime is 215618149. The reversal of 215618140 is 41816512.

It is a junction number, because it is equal to n+sod(n) for n = 215618099 and 215618108.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215618149) 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 31 ways as a sum of consecutive naturals, for example, 1645875 + ... + 1646005.

It is an arithmetic number, because the mean of its divisors is an integer number (5189184).

Almost surely, 2^215618140 is an apocalyptic number.

215618140 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 215618140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (249080832).

215618140 is an abundant number, since it is smaller than the sum of its proper divisors (282543524).

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

215618140 is a wasteful number, since it uses less digits than its factorization.

215618140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 307 (or 305 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 28.

The square root of 215618140 is about 14683.9415689385. The cubic root of 215618140 is about 599.6462173633.

The spelling of 215618140 in words is "two hundred fifteen million, six hundred eighteen thousand, one hundred forty".