161044621 has 4 divisors (see below), whose sum is σ = 170517852. Its totient is φ = 151571392.

The previous prime is 161044603. The next prime is 161044633. The reversal of 161044621 is 126440161.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 126440161 = 73 ⋅1732057.

It can be written as a sum of positive squares in 2 ways, for example, as 114190596 + 46854025 = 10686^2 + 6845^2 .

It is a cyclic number.

It is not a de Polignac number, because 161044621 - 2⁷ = 161044493 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161044661) 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, 4736590 + ... + 4736623.

It is an arithmetic number, because the mean of its divisors is an integer number (42629463).

Almost surely, 2^161044621 is an apocalyptic number.

It is an amenable number.

161044621 is a deficient number, since it is larger than the sum of its proper divisors (9473231).

161044621 is an equidigital number, since it uses as much as digits as its factorization.

161044621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9473230.

The product of its (nonzero) digits is 1152, while the sum is 25.

The square root of 161044621 is about 12690.3357323595. The cubic root of 161044621 is about 544.0624353891.

Adding to 161044621 its reverse (126440161), we get a palindrome (287484782).

The spelling of 161044621 in words is "one hundred sixty-one million, forty-four thousand, six hundred twenty-one".