161520551515 has 8 divisors (see below), whose sum is σ = 193925048688. Its totient is φ = 129149516640.

The previous prime is 161520551509. The next prime is 161520551531. The reversal of 161520551515 is 515155025161.

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

It is not a de Polignac number, because 161520551515 - 2³⁵ = 127160813147 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8354952 + ... + 8374261.

It is an arithmetic number, because the mean of its divisors is an integer number (24240631086).

Almost surely, 2^161520551515 is an apocalyptic number.

161520551515 is a deficient number, since it is larger than the sum of its proper divisors (32404497173).

161520551515 is a wasteful number, since it uses less digits than its factorization.

161520551515 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16731149.

The product of its (nonzero) digits is 37500, while the sum is 37.

Adding to 161520551515 its reverse (515155025161), we get a palindrome (676675576676).

The spelling of 161520551515 in words is "one hundred sixty-one billion, five hundred twenty million, five hundred fifty-one thousand, five hundred fifteen".