16106781 has 4 divisors (see below), whose sum is σ = 21475712. Its totient is φ = 10737852.

The previous prime is 16106777. The next prime is 16106789. The reversal of 16106781 is 18760161.

It is a happy number.

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 not a de Polignac number, because 16106781 - 2² = 16106777 is a prime.

It is a super-2 number, since 2×16106781² = 518856788363922, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16106789) 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, 2684461 + ... + 2684466.

It is an arithmetic number, because the mean of its divisors is an integer number (5368928).

Almost surely, 2^16106781 is an apocalyptic number.

It is an amenable number.

16106781 is a deficient number, since it is larger than the sum of its proper divisors (5368931).

16106781 is an equidigital number, since it uses as much as digits as its factorization.

16106781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5368930.

The product of its (nonzero) digits is 2016, while the sum is 30.

The square root of 16106781 is about 4013.3254291174. The cubic root of 16106781 is about 252.5435326700.

The spelling of 16106781 in words is "sixteen million, one hundred six thousand, seven hundred eighty-one".