16421593 has 2 divisors, whose sum is σ = 16421594. Its totient is φ = 16421592.

The previous prime is 16421579. The next prime is 16421597. The reversal of 16421593 is 39512461.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15776784 + 644809 = 3972^2 + 803^2 .

It is a cyclic number.

It is not a de Polignac number, because 16421593 - 2²¹ = 14324441 is a prime.

It is not a weakly prime, because it can be changed into another prime (16421597) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8210796 + 8210797.

It is an arithmetic number, because the mean of its divisors is an integer number (8210797).

Almost surely, 2^16421593 is an apocalyptic number.

It is an amenable number.

16421593 is a deficient number, since it is larger than the sum of its proper divisors (1).

16421593 is an equidigital number, since it uses as much as digits as its factorization.

16421593 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6480, while the sum is 31.

The square root of 16421593 is about 4052.3564749415. The cubic root of 16421593 is about 254.1782750349.

The spelling of 16421593 in words is "sixteen million, four hundred twenty-one thousand, five hundred ninety-three".