215215478 has 16 divisors (see below), whose sum is σ = 350151984. Its totient is φ = 98807040.

The previous prime is 215215477. The next prime is 215215487. The reversal of 215215478 is 874512512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215215477) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 75800 + ... + 78587.

It is an arithmetic number, because the mean of its divisors is an integer number (21884499).

Almost surely, 2^215215478 is an apocalyptic number.

215215478 is a deficient number, since it is larger than the sum of its proper divisors (134936506).

215215478 is a wasteful number, since it uses less digits than its factorization.

215215478 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 154447.

The product of its digits is 22400, while the sum is 35.

The square root of 215215478 is about 14670.2241973325. The cubic root of 215215478 is about 599.2727095112.

The spelling of 215215478 in words is "two hundred fifteen million, two hundred fifteen thousand, four hundred seventy-eight".