216470581 has 2 divisors, whose sum is σ = 216470582. Its totient is φ = 216470580.

The previous prime is 216470567. The next prime is 216470593. The reversal of 216470581 is 185074612.

216470581 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 117288900 + 99181681 = 10830^2 + 9959^2 .

It is a cyclic number.

It is not a de Polignac number, because 216470581 - 2⁷ = 216470453 is a prime.

It is a super-2 number, since 2×216470581² = 93719024876955122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (216470521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108235290 + 108235291.

It is an arithmetic number, because the mean of its divisors is an integer number (108235291).

Almost surely, 2^216470581 is an apocalyptic number.

It is an amenable number.

216470581 is a deficient number, since it is larger than the sum of its proper divisors (1).

216470581 is an equidigital number, since it uses as much as digits as its factorization.

216470581 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13440, while the sum is 34.

The square root of 216470581 is about 14712.9392372836. The cubic root of 216470581 is about 600.4354071061.

The spelling of 216470581 in words is "two hundred sixteen million, four hundred seventy thousand, five hundred eighty-one".