161521134635 has 16 divisors (see below), whose sum is σ = 221524314816. Its totient is φ = 110752541568.

The previous prime is 161521134623. The next prime is 161521134653. The reversal of 161521134635 is 536431125161.

It is a cyclic number.

It is not a de Polignac number, because 161521134635 - 2⁶ = 161521134571 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 842609 + ... + 1016381.

It is an arithmetic number, because the mean of its divisors is an integer number (13845269676).

Almost surely, 2^161521134635 is an apocalyptic number.

161521134635 is a deficient number, since it is larger than the sum of its proper divisors (60003180181).

161521134635 is a wasteful number, since it uses less digits than its factorization.

161521134635 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 200342.

The product of its digits is 64800, while the sum is 38.

Adding to 161521134635 its reverse (536431125161), we get a palindrome (697952259796).

The spelling of 161521134635 in words is "one hundred sixty-one billion, five hundred twenty-one million, one hundred thirty-four thousand, six hundred thirty-five".