161054981 has 2 divisors, whose sum is σ = 161054982. Its totient is φ = 161054980.

The previous prime is 161054977. The next prime is 161054983. The reversal of 161054981 is 189450161.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 157904356 + 3150625 = 12566^2 + 1775^2 .

It is an emirp because it is prime and its reverse (189450161) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 161054981 - 2² = 161054977 is a prime.

It is a super-2 number, since 2×161054981² = 51877413809820722, which contains 22 as substring.

Together with 161054983, it forms a pair of twin primes.

It is a Chen prime.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (161054983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80527490 + 80527491.

It is an arithmetic number, because the mean of its divisors is an integer number (80527491).

Almost surely, 2^161054981 is an apocalyptic number.

It is an amenable number.

161054981 is a deficient number, since it is larger than the sum of its proper divisors (1).

161054981 is an equidigital number, since it uses as much as digits as its factorization.

161054981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8640, while the sum is 35.

The square root of 161054981 is about 12690.7439104254. The cubic root of 161054981 is about 544.0741016506.

The spelling of 161054981 in words is "one hundred sixty-one million, fifty-four thousand, nine hundred eighty-one".