16381961 has 2 divisors, whose sum is σ = 16381962. Its totient is φ = 16381960.

The previous prime is 16381891. The next prime is 16381979. The reversal of 16381961 is 16918361.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12559936 + 3822025 = 3544^2 + 1955^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16381961 is a prime.

It is not a weakly prime, because it can be changed into another prime (16381061) 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 as a sum of consecutive naturals, namely, 8190980 + 8190981.

It is an arithmetic number, because the mean of its divisors is an integer number (8190981).

Almost surely, 2^16381961 is an apocalyptic number.

It is an amenable number.

16381961 is a deficient number, since it is larger than the sum of its proper divisors (1).

16381961 is an equidigital number, since it uses as much as digits as its factorization.

16381961 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 7776, while the sum is 35.

The square root of 16381961 is about 4047.4635267041. The cubic root of 16381961 is about 253.9736317100.

The spelling of 16381961 in words is "sixteen million, three hundred eighty-one thousand, nine hundred sixty-one".