215982649 has 4 divisors (see below), whose sum is σ = 216451620. Its totient is φ = 215513680.

The previous prime is 215982647. The next prime is 215982703. The reversal of 215982649 is 946289512.

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 59907600 + 156075049 = 7740^2 + 12493^2 .

It is a cyclic number.

It is not a de Polignac number, because 215982649 - 2¹ = 215982647 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 215982599 and 215982608.

It is not an unprimeable number, because it can be changed into a prime (215982647) 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, 233794 + ... + 234715.

It is an arithmetic number, because the mean of its divisors is an integer number (54112905).

Almost surely, 2^215982649 is an apocalyptic number.

It is an amenable number.

215982649 is a deficient number, since it is larger than the sum of its proper divisors (468971).

215982649 is an equidigital number, since it uses as much as digits as its factorization.

215982649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 468970.

The product of its digits is 311040, while the sum is 46.

The square root of 215982649 is about 14696.3481518369. The cubic root of 215982649 is about 599.9839338291.

The spelling of 215982649 in words is "two hundred fifteen million, nine hundred eighty-two thousand, six hundred forty-nine".