165542245561 has 32 divisors (see below), whose sum is σ = 207138152448. Its totient is φ = 128527439040.

The previous prime is 165542245543. The next prime is 165542245651.

165542245561 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 165542245561 - 2¹³ = 165542237369 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165542245541) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 27555220 + ... + 27561226.

It is an arithmetic number, because the mean of its divisors is an integer number (6473067264).

Almost surely, 2^165542245561 is an apocalyptic number.

165542245561 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

165542245561 is a deficient number, since it is larger than the sum of its proper divisors (41595906887).

165542245561 is a wasteful number, since it uses less digits than its factorization.

165542245561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7261.

The product of its digits is 1440000, while the sum is 46.

The spelling of 165542245561 in words is "one hundred sixty-five billion, five hundred forty-two million, two hundred forty-five thousand, five hundred sixty-one".