215405768 has 12 divisors (see below), whose sum is σ = 403963665. Its totient is φ = 107682128.

The previous prime is 215405683. The next prime is 215405803. The reversal of 215405768 is 867504512.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

215405768 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 195496324 + 19909444 = 13982^2 + 4462^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=10378.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 38918 + ... + 44106.

Almost surely, 2^215405768 is an apocalyptic number.

It is an amenable number.

215405768 is a deficient number, since it is larger than the sum of its proper divisors (188557897).

215405768 is an frugal number, since it uses more digits than its factorization.

215405768 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10384 (or 5191 counting only the distinct ones).

The product of its (nonzero) digits is 67200, while the sum is 38.

The square root of 215405768 is about 14676.7083503080. The cubic root of 215405768 is about 599.4492798520.

The spelling of 215405768 in words is "two hundred fifteen million, four hundred five thousand, seven hundred sixty-eight".