215930609 has 2 divisors, whose sum is σ = 215930610. Its totient is φ = 215930608.

The previous prime is 215930587. The next prime is 215930707. The reversal of 215930609 is 906039512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 148230625 + 67699984 = 12175^2 + 8228^2 .

It is a cyclic number.

It is not a de Polignac number, because 215930609 - 2¹⁶ = 215865073 is a prime.

It is a super-2 number, since 2×215930609² = 93252055806221762, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (215935609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 107965304 + 107965305.

It is an arithmetic number, because the mean of its divisors is an integer number (107965305).

Almost surely, 2^215930609 is an apocalyptic number.

It is an amenable number.

215930609 is a deficient number, since it is larger than the sum of its proper divisors (1).

215930609 is an equidigital number, since it uses as much as digits as its factorization.

215930609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 14580, while the sum is 35.

The square root of 215930609 is about 14694.5775373095. The cubic root of 215930609 is about 599.9357421925.

It can be divided in two parts, 2159 and 30609, that added together give a 15-th power (32768 = 2¹⁵).

The spelling of 215930609 in words is "two hundred fifteen million, nine hundred thirty thousand, six hundred nine".