215161540 has 24 divisors (see below), whose sum is σ = 492916032. Its totient is φ = 78240480.

The previous prime is 215161519. The next prime is 215161543. The reversal of 215161540 is 45161512.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (215161543) 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 7 ways as a sum of consecutive naturals, for example, 488784 + ... + 489223.

It is an arithmetic number, because the mean of its divisors is an integer number (20538168).

Almost surely, 2^215161540 is an apocalyptic number.

215161540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

215161540 is an abundant number, since it is smaller than the sum of its proper divisors (277754492).

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

215161540 is a wasteful number, since it uses less digits than its factorization.

215161540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 978027 (or 978025 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 25.

The square root of 215161540 is about 14668.3857325883. The cubic root of 215161540 is about 599.2226414392. Note that the first 3 decimals are identical.

The spelling of 215161540 in words is "two hundred fifteen million, one hundred sixty-one thousand, five hundred forty".