65661289 has 2 divisors, whose sum is σ = 65661290. Its totient is φ = 65661288.

The previous prime is 65661247. The next prime is 65661331. The reversal of 65661289 is 98216656.

It is a balanced prime because it is at equal distance from previous prime (65661247) and next prime (65661331).

It can be written as a sum of positive squares in only one way, i.e., 51912025 + 13749264 = 7205^2 + 3708^2 .

It is a cyclic number.

It is not a de Polignac number, because 65661289 - 2²³ = 57272681 is a prime.

It is a super-2 number, since 2×65661289² = 8622809746283042, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (65667289) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32830644 + 32830645.

It is an arithmetic number, because the mean of its divisors is an integer number (32830645).

Almost surely, 2^65661289 is an apocalyptic number.

It is an amenable number.

65661289 is a deficient number, since it is larger than the sum of its proper divisors (1).

65661289 is an equidigital number, since it uses as much as digits as its factorization.

65661289 is an evil number, because the sum of its binary digits is even.

The product of its digits is 155520, while the sum is 43.

The square root of 65661289 is about 8103.1653691628. The cubic root of 65661289 is about 403.4314966468.

The spelling of 65661289 in words is "sixty-five million, six hundred sixty-one thousand, two hundred eighty-nine".