16051921 has 2 divisors, whose sum is σ = 16051922. Its totient is φ = 16051920.

The previous prime is 16051909. The next prime is 16051933. The reversal of 16051921 is 12915061.

It is a balanced prime because it is at equal distance from previous prime (16051909) and next prime (16051933).

It can be written as a sum of positive squares in only one way, i.e., 10595025 + 5456896 = 3255^2 + 2336^2 .

It is an emirp because it is prime and its reverse (12915061) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16051921 - 2²¹ = 13954769 is a prime.

It is not a weakly prime, because it can be changed into another prime (16051991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8025960 + 8025961.

It is an arithmetic number, because the mean of its divisors is an integer number (8025961).

Almost surely, 2^16051921 is an apocalyptic number.

It is an amenable number.

16051921 is a deficient number, since it is larger than the sum of its proper divisors (1).

16051921 is an equidigital number, since it uses as much as digits as its factorization.

16051921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 540, while the sum is 25.

The square root of 16051921 is about 4006.4848683104. The cubic root of 16051921 is about 252.2564838459.

Adding to 16051921 its reverse (12915061), we get a palindrome (28966982).

The spelling of 16051921 in words is "sixteen million, fifty-one thousand, nine hundred twenty-one".