215994473 has 4 divisors (see below), whose sum is σ = 219535428. Its totient is φ = 212453520.

The previous prime is 215994439. The next prime is 215994481. The reversal of 215994473 is 374499512.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5396329 + 210598144 = 2323^2 + 14512^2 .

It is a cyclic number.

It is not a de Polignac number, because 215994473 - 2⁸ = 215994217 is a prime.

It is a super-2 number, since 2×215994473² = 93307224733095458, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (215997473) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1770386 + ... + 1770507.

It is an arithmetic number, because the mean of its divisors is an integer number (54883857).

Almost surely, 2^215994473 is an apocalyptic number.

It is an amenable number.

215994473 is a deficient number, since it is larger than the sum of its proper divisors (3540955).

215994473 is an equidigital number, since it uses as much as digits as its factorization.

215994473 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3540954.

The product of its digits is 272160, while the sum is 44.

The square root of 215994473 is about 14696.7504231378. The cubic root of 215994473 is about 599.9948823638.

The spelling of 215994473 in words is "two hundred fifteen million, nine hundred ninety-four thousand, four hundred seventy-three".