215645420 has 12 divisors (see below), whose sum is σ = 452855424. Its totient is φ = 86258160.

The previous prime is 215645399. The next prime is 215645429. The reversal of 215645420 is 24546512.

It is not an unprimeable number, because it can be changed into a prime (215645429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5391116 + ... + 5391155.

It is an arithmetic number, because the mean of its divisors is an integer number (37737952).

Almost surely, 2^215645420 is an apocalyptic number.

215645420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

215645420 is an abundant number, since it is smaller than the sum of its proper divisors (237210004).

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

215645420 is a wasteful number, since it uses less digits than its factorization.

215645420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10782280 (or 10782278 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 29.

The square root of 215645420 is about 14684.8704454619. The cubic root of 215645420 is about 599.6715053701.

The spelling of 215645420 in words is "two hundred fifteen million, six hundred forty-five thousand, four hundred twenty".