161356001 has 4 divisors (see below), whose sum is σ = 165717012. Its totient is φ = 156994992.

The previous prime is 161355991. The next prime is 161356003. The reversal of 161356001 is 100653161.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 100653161 = 7 ⋅14379023.

It can be written as a sum of positive squares in 2 ways, for example, as 101525776 + 59830225 = 10076^2 + 7735^2 .

It is a cyclic number.

It is not a de Polignac number, because 161356001 - 2¹⁸ = 161093857 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161356003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2180450 + ... + 2180523.

It is an arithmetic number, because the mean of its divisors is an integer number (41429253).

Almost surely, 2^161356001 is an apocalyptic number.

It is an amenable number.

161356001 is a deficient number, since it is larger than the sum of its proper divisors (4361011).

161356001 is an equidigital number, since it uses as much as digits as its factorization.

161356001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4361010.

The product of its (nonzero) digits is 540, while the sum is 23.

The square root of 161356001 is about 12702.5981987938. The cubic root of 161356001 is about 544.4128581317.

The spelling of 161356001 in words is "one hundred sixty-one million, three hundred fifty-six thousand, one".