161617577745 has 16 divisors (see below), whose sum is σ = 278479518912. Its totient is φ = 79565576640.

The previous prime is 161617577743. The next prime is 161617577753. The reversal of 161617577745 is 547775716161.

It is not a de Polignac number, because 161617577745 - 2¹ = 161617577743 is a prime.

It is a super-2 number, since 2×161617577745² (a number of 23 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (161617577741) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 414403851 + ... + 414404240.

It is an arithmetic number, because the mean of its divisors is an integer number (17404969932).

Almost surely, 2^161617577745 is an apocalyptic number.

161617577745 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

161617577745 is a deficient number, since it is larger than the sum of its proper divisors (116861941167).

161617577745 is a wasteful number, since it uses less digits than its factorization.

161617577745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 828808112.

The product of its digits is 8643600, while the sum is 57.

The spelling of 161617577745 in words is "one hundred sixty-one billion, six hundred seventeen million, five hundred seventy-seven thousand, seven hundred forty-five".