1641691069 has 2 divisors, whose sum is σ = 1641691070. Its totient is φ = 1641691068.

The previous prime is 1641691001. The next prime is 1641691091. The reversal of 1641691069 is 9601961461.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1028484900 + 613206169 = 32070^2 + 24763^2 .

It is a cyclic number.

It is not a de Polignac number, because 1641691069 - 2¹⁵ = 1641658301 is a prime.

It is a super-2 number, since 2×1641691069² = 5390299132068725522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1641691169) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 820845534 + 820845535.

It is an arithmetic number, because the mean of its divisors is an integer number (820845535).

Almost surely, 2^1641691069 is an apocalyptic number.

It is an amenable number.

1641691069 is a deficient number, since it is larger than the sum of its proper divisors (1).

1641691069 is an equidigital number, since it uses as much as digits as its factorization.

1641691069 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 69984, while the sum is 43.

The square root of 1641691069 is about 40517.7870693847. The cubic root of 1641691069 is about 1179.6789007092.

The spelling of 1641691069 in words is "one billion, six hundred forty-one million, six hundred ninety-one thousand, sixty-nine".