161610831535 has 4 divisors (see below), whose sum is σ = 193932997848. Its totient is φ = 129288665224.

The previous prime is 161610831509. The next prime is 161610831589. The reversal of 161610831535 is 535138016161.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 161610831535 - 2¹¹ = 161610829487 is a prime.

It is a super-2 number, since 2×161610831535² (a number of 23 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16161083149 + ... + 16161083158.

It is an arithmetic number, because the mean of its divisors is an integer number (48483249462).

Almost surely, 2^161610831535 is an apocalyptic number.

161610831535 is a deficient number, since it is larger than the sum of its proper divisors (32322166313).

161610831535 is an equidigital number, since it uses as much as digits as its factorization.

161610831535 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32322166312.

The product of its (nonzero) digits is 64800, while the sum is 40.

Adding to 161610831535 its reverse (535138016161), we get a palindrome (696748847696).

The spelling of 161610831535 in words is "one hundred sixty-one billion, six hundred ten million, eight hundred thirty-one thousand, five hundred thirty-five".