16057781 has 4 divisors (see below), whose sum is σ = 16360812. Its totient is φ = 15754752.

The previous prime is 16057759. The next prime is 16057787. The reversal of 16057781 is 18775061.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5134756 + 10923025 = 2266^2 + 3305^2 .

It is a cyclic number.

It is not a de Polignac number, because 16057781 - 2¹⁴ = 16041397 is a prime.

It is a super-2 number, since 2×16057781² = 515704661287922, 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 (16057787) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 151436 + ... + 151541.

It is an arithmetic number, because the mean of its divisors is an integer number (4090203).

Almost surely, 2^16057781 is an apocalyptic number.

It is an amenable number.

16057781 is a deficient number, since it is larger than the sum of its proper divisors (303031).

16057781 is an equidigital number, since it uses as much as digits as its factorization.

16057781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 303030.

The product of its (nonzero) digits is 11760, while the sum is 35.

The square root of 16057781 is about 4007.2161159588. The cubic root of 16057781 is about 252.2871768109.

The spelling of 16057781 in words is "sixteen million, fifty-seven thousand, seven hundred eighty-one".