161855297792929 has 16 divisors (see below), whose sum is σ = 181951369870480. Its totient is φ = 142983855970560.

The previous prime is 161855297792887. The next prime is 161855297792933. The reversal of 161855297792929 is 929297792558161.

It can be written as a sum of positive squares in 8 ways, for example, as 2110395398400 + 159744902394529 = 1452720^2 + 12639023^2 .

It is a cyclic number.

It is not a de Polignac number, because 161855297792929 - 2¹¹ = 161855297790881 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161855297792129) 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, 2758146894 + ... + 2758205575.

It is an arithmetic number, because the mean of its divisors is an integer number (11371960616905).

Almost surely, 2^{161855297792929} is an apocalyptic number.

It is an amenable number.

161855297792929 is a deficient number, since it is larger than the sum of its proper divisors (20096072077551).

161855297792929 is a wasteful number, since it uses less digits than its factorization.

161855297792929 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5516352580.

The product of its digits is 3086294400, while the sum is 82.

The spelling of 161855297792929 in words is "one hundred sixty-one trillion, eight hundred fifty-five billion, two hundred ninety-seven million, seven hundred ninety-two thousand, nine hundred twenty-nine".