16105981 has 4 divisors (see below), whose sum is σ = 16202592. Its totient is φ = 16009372.

The previous prime is 16105963. The next prime is 16105993. The reversal of 16105981 is 18950161.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 16105981 - 2¹⁷ = 15974909 is a prime.

It is a super-2 number, since 2×16105981² = 518805247944722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16105931) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 48055 + ... + 48388.

It is an arithmetic number, because the mean of its divisors is an integer number (4050648).

Almost surely, 2^16105981 is an apocalyptic number.

It is an amenable number.

16105981 is a deficient number, since it is larger than the sum of its proper divisors (96611).

16105981 is an equidigital number, since it uses as much as digits as its factorization.

16105981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 96610.

The product of its (nonzero) digits is 2160, while the sum is 31.

The square root of 16105981 is about 4013.2257599094. The cubic root of 16105981 is about 252.5393514462.

The spelling of 16105981 in words is "sixteen million, one hundred five thousand, nine hundred eighty-one".