161355745 has 4 divisors (see below), whose sum is σ = 193626900. Its totient is φ = 129084592.

The previous prime is 161355743. The next prime is 161355773. The reversal of 161355745 is 547553161.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 547553161 = 347 ⋅1577963.

It can be written as a sum of positive squares in 2 ways, for example, as 69022864 + 92332881 = 8308^2 + 9609^2 .

It is a cyclic number.

It is not a de Polignac number, because 161355745 - 2¹ = 161355743 is a prime.

It is not an unprimeable number, because it can be changed into a prime (161355743) 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, 16135570 + ... + 16135579.

It is an arithmetic number, because the mean of its divisors is an integer number (48406725).

Almost surely, 2^161355745 is an apocalyptic number.

It is an amenable number.

161355745 is a deficient number, since it is larger than the sum of its proper divisors (32271155).

161355745 is an equidigital number, since it uses as much as digits as its factorization.

161355745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32271154.

The product of its digits is 63000, while the sum is 37.

The square root of 161355745 is about 12702.5881221112. The cubic root of 161355745 is about 544.4125702181.

The spelling of 161355745 in words is "one hundred sixty-one million, three hundred fifty-five thousand, seven hundred forty-five".