2061665569 has 2 divisors, whose sum is σ = 2061665570. Its totient is φ = 2061665568.

The previous prime is 2061665537. The next prime is 2061665579. The reversal of 2061665569 is 9655661602.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1793099025 + 268566544 = 42345^2 + 16388^2 .

It is a cyclic number.

It is not a de Polignac number, because 2061665569 - 2⁵ = 2061665537 is a prime.

It is a super-2 number, since 2×2061665569² = 8500929836800187522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (2061665519) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1030832784 + 1030832785.

It is an arithmetic number, because the mean of its divisors is an integer number (1030832785).

Almost surely, 2^2061665569 is an apocalyptic number.

It is an amenable number.

2061665569 is a deficient number, since it is larger than the sum of its proper divisors (1).

2061665569 is an equidigital number, since it uses as much as digits as its factorization.

2061665569 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 583200, while the sum is 46.

The square root of 2061665569 is about 45405.5675991392. The cubic root of 2061665569 is about 1272.7391576409.

The spelling of 2061665569 in words is "two billion, sixty-one million, six hundred sixty-five thousand, five hundred sixty-nine".