16765421 has 2 divisors, whose sum is σ = 16765422. Its totient is φ = 16765420.

The previous prime is 16765387. The next prime is 16765439. The reversal of 16765421 is 12456761.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12709225 + 4056196 = 3565^2 + 2014^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16765421 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16765121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8382710 + 8382711.

It is an arithmetic number, because the mean of its divisors is an integer number (8382711).

Almost surely, 2^16765421 is an apocalyptic number.

It is an amenable number.

16765421 is a deficient number, since it is larger than the sum of its proper divisors (1).

16765421 is an equidigital number, since it uses as much as digits as its factorization.

16765421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10080, while the sum is 32.

The square root of 16765421 is about 4094.5599275136. The cubic root of 16765421 is about 255.9399934632.

The spelling of 16765421 in words is "sixteen million, seven hundred sixty-five thousand, four hundred twenty-one".