1691534078371 has 2 divisors, whose sum is σ = 1691534078372. Its totient is φ = 1691534078370.

The previous prime is 1691534078357. The next prime is 1691534078407. The reversal of 1691534078371 is 1738704351961.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1691534078371 - 2⁷ = 1691534078243 is a prime.

It is a super-2 number, since 2×1691534078371² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1691534058371) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 845767039185 + 845767039186.

It is an arithmetic number, because the mean of its divisors is an integer number (845767039186).

Almost surely, 2^{1691534078371} is an apocalyptic number.

1691534078371 is a deficient number, since it is larger than the sum of its proper divisors (1).

1691534078371 is an equidigital number, since it uses as much as digits as its factorization.

1691534078371 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3810240, while the sum is 55.

The spelling of 1691534078371 in words is "one trillion, six hundred ninety-one billion, five hundred thirty-four million, seventy-eight thousand, three hundred seventy-one".