161510641 has 4 divisors (see below), whose sum is σ = 162992500. Its totient is φ = 160028784.

The previous prime is 161510627. The next prime is 161510653. The reversal of 161510641 is 146015161.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 146015161 = 3203 ⋅45587.

It can be written as a sum of positive squares in 2 ways, for example, as 116553616 + 44957025 = 10796^2 + 6705^2 .

It is a cyclic number.

It is not a de Polignac number, because 161510641 - 2¹³ = 161502449 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (161511641) 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, 740766 + ... + 740983.

It is an arithmetic number, because the mean of its divisors is an integer number (40748125).

Almost surely, 2^161510641 is an apocalyptic number.

It is an amenable number.

161510641 is a deficient number, since it is larger than the sum of its proper divisors (1481859).

161510641 is a wasteful number, since it uses less digits than its factorization.

161510641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1481858.

The product of its (nonzero) digits is 720, while the sum is 25.

The square root of 161510641 is about 12708.6836847881. The cubic root of 161510641 is about 544.5867203237.

The spelling of 161510641 in words is "one hundred sixty-one million, five hundred ten thousand, six hundred forty-one".