215502540 has 96 divisors (see below), whose sum is σ = 697019904. Its totient is φ = 49167360.

The previous prime is 215502533. The next prime is 215502559. The reversal of 215502540 is 45205512.

It is a happy number.

215502540 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 215502540.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1617 + ... + 20823.

It is an arithmetic number, because the mean of its divisors is an integer number (7260624).

Almost surely, 2^215502540 is an apocalyptic number.

215502540 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 215502540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (348509952).

215502540 is an abundant number, since it is smaller than the sum of its proper divisors (481517364).

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

215502540 is a wasteful number, since it uses less digits than its factorization.

215502540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19247 (or 19245 counting only the distinct ones).

The product of its (nonzero) digits is 2000, while the sum is 24.

The square root of 215502540 is about 14680.0047683916. The cubic root of 215502540 is about 599.5390348314.

It can be divided in two parts, 21550 and 2540, that added together give a triangular number (24090 = T₂₁₉).

The spelling of 215502540 in words is "two hundred fifteen million, five hundred two thousand, five hundred forty".