161691526507 has 8 divisors (see below), whose sum is σ = 188276926176. Its totient is φ = 135977779392.

The previous prime is 161691526463. The next prime is 161691526541. The reversal of 161691526507 is 705625196161.

161691526507 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 161691526507 - 2¹¹ = 161691524459 is a prime.

It is a super-2 number, since 2×161691526507² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161691526207) 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 in 7 ways as a sum of consecutive naturals, for example, 217912738 + ... + 217913479.

It is an arithmetic number, because the mean of its divisors is an integer number (23534615772).

Almost surely, 2^161691526507 is an apocalyptic number.

161691526507 is a deficient number, since it is larger than the sum of its proper divisors (26585399669).

161691526507 is an equidigital number, since it uses as much as digits as its factorization.

161691526507 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 435826277.

The product of its (nonzero) digits is 680400, while the sum is 49.

The spelling of 161691526507 in words is "one hundred sixty-one billion, six hundred ninety-one million, five hundred twenty-six thousand, five hundred seven".