16378081 has 2 divisors, whose sum is σ = 16378082. Its totient is φ = 16378080.

The previous prime is 16378051. The next prime is 16378091. The reversal of 16378081 is 18087361.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16329681 + 48400 = 4041^2 + 220^2 .

It is a cyclic number.

It is not a de Polignac number, because 16378081 - 2¹¹ = 16376033 is a prime.

It is a super-2 number, since 2×16378081² = 536483074485122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (16378051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8189040 + 8189041.

It is an arithmetic number, because the mean of its divisors is an integer number (8189041).

Almost surely, 2^16378081 is an apocalyptic number.

It is an amenable number.

16378081 is a deficient number, since it is larger than the sum of its proper divisors (1).

16378081 is an equidigital number, since it uses as much as digits as its factorization.

16378081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8064, while the sum is 34.

The square root of 16378081 is about 4046.9841857858. The cubic root of 16378081 is about 253.9535792572.

The spelling of 16378081 in words is "sixteen million, three hundred seventy-eight thousand, eighty-one".