161606061615989 has 4 divisors (see below), whose sum is σ = 168632412121056. Its totient is φ = 154579711110924.

The previous prime is 161606061615983. The next prime is 161606061615997. The reversal of 161606061615989 is 989516160606161.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-161606061615989 is a prime.

It is a super-2 number, since 2×161606061615989² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161606061615983) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3513175252499 + ... + 3513175252544.

It is an arithmetic number, because the mean of its divisors is an integer number (42158103030264).

Almost surely, 2^{161606061615989} is an apocalyptic number.

It is an amenable number.

161606061615989 is a deficient number, since it is larger than the sum of its proper divisors (7026350505067).

161606061615989 is an equidigital number, since it uses as much as digits as its factorization.

161606061615989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7026350505066.

The product of its (nonzero) digits is 25194240, while the sum is 65.

The spelling of 161606061615989 in words is "one hundred sixty-one trillion, six hundred six billion, sixty-one million, six hundred fifteen thousand, nine hundred eighty-nine".