161238381 has 8 divisors (see below), whose sum is σ = 218193504. Its totient is φ = 105887760.

The previous prime is 161238379. The next prime is 161238403. The reversal of 161238381 is 183832161.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 161238381 - 2¹ = 161238379 is a prime.

It is a super-2 number, since 2×161238381² = 51995631015002322, which contains 22 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161238481) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 400890 + ... + 401291.

It is an arithmetic number, because the mean of its divisors is an integer number (27274188).

Almost surely, 2^161238381 is an apocalyptic number.

It is an amenable number.

161238381 is a deficient number, since it is larger than the sum of its proper divisors (56955123).

161238381 is an equidigital number, since it uses as much as digits as its factorization.

161238381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 802251.

The product of its digits is 6912, while the sum is 33.

The square root of 161238381 is about 12697.9675932804. The cubic root of 161238381 is about 544.2805432393.

It can be divided in two parts, 1612 and 38381, that added together give a palindrome (39993).

The spelling of 161238381 in words is "one hundred sixty-one million, two hundred thirty-eight thousand, three hundred eighty-one".