1661009263 has 2 divisors, whose sum is σ = 1661009264. Its totient is φ = 1661009262.

The previous prime is 1661009219. The next prime is 1661009269. The reversal of 1661009263 is 3629001661.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1661009263 - 2²⁵ = 1627454831 is a prime.

It is a super-3 number, since 3×1661009263³ (a number of 29 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1661009269) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 830504631 + 830504632.

It is an arithmetic number, because the mean of its divisors is an integer number (830504632).

Almost surely, 2^1661009263 is an apocalyptic number.

1661009263 is a deficient number, since it is larger than the sum of its proper divisors (1).

1661009263 is an equidigital number, since it uses as much as digits as its factorization.

1661009263 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11664, while the sum is 34.

The square root of 1661009263 is about 40755.4813859437. The cubic root of 1661009263 is about 1184.2880619769.

The spelling of 1661009263 in words is "one billion, six hundred sixty-one million, nine thousand, two hundred sixty-three".