161387641 has 2 divisors, whose sum is σ = 161387642. Its totient is φ = 161387640.

The previous prime is 161387627. The next prime is 161387659. The reversal of 161387641 is 146783161.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 158760000 + 2627641 = 12600^2 + 1621^2 .

It is a cyclic number.

It is not a de Polignac number, because 161387641 - 2⁵ = 161387609 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 161387641.

It is not a weakly prime, because it can be changed into another prime (161387621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80693820 + 80693821.

It is an arithmetic number, because the mean of its divisors is an integer number (80693821).

Almost surely, 2^161387641 is an apocalyptic number.

It is an amenable number.

161387641 is a deficient number, since it is larger than the sum of its proper divisors (1).

161387641 is an equidigital number, since it uses as much as digits as its factorization.

161387641 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 24192, while the sum is 37.

The square root of 161387641 is about 12703.8435522483. The cubic root of 161387641 is about 544.4484401098.

The spelling of 161387641 in words is "one hundred sixty-one million, three hundred eighty-seven thousand, six hundred forty-one".