16481381 has 12 divisors (see below), whose sum is σ = 20011488. Its totient is φ = 13294272.

The previous prime is 16481329. The next prime is 16481383. The reversal of 16481381 is 18318461.

It is a happy number.

It is not a de Polignac number, because 16481381 - 2¹⁰ = 16480357 is a prime.

It is a super-2 number, since 2×16481381² = 543271839334322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16481383) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2051 + ... + 6096.

It is an arithmetic number, because the mean of its divisors is an integer number (1667624).

Almost surely, 2^16481381 is an apocalyptic number.

It is an amenable number.

16481381 is a deficient number, since it is larger than the sum of its proper divisors (3530107).

16481381 is an equidigital number, since it uses as much as digits as its factorization.

16481381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8188 (or 8171 counting only the distinct ones).

The product of its digits is 4608, while the sum is 32.

The square root of 16481381 is about 4059.7267149403. The cubic root of 16481381 is about 254.4863735446.

The spelling of 16481381 in words is "sixteen million, four hundred eighty-one thousand, three hundred eighty-one".