16689401 has 2 divisors, whose sum is σ = 16689402. Its totient is φ = 16689400.

The previous prime is 16689397. The next prime is 16689437. The reversal of 16689401 is 10498661.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16613776 + 75625 = 4076^2 + 275^2 .

It is a cyclic number.

It is not a de Polignac number, because 16689401 - 2² = 16689397 is a prime.

It is a super-2 number, since 2×16689401² = 557072211477602, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (16689481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8344700 + 8344701.

It is an arithmetic number, because the mean of its divisors is an integer number (8344701).

Almost surely, 2^16689401 is an apocalyptic number.

It is an amenable number.

16689401 is a deficient number, since it is larger than the sum of its proper divisors (1).

16689401 is an equidigital number, since it uses as much as digits as its factorization.

16689401 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10368, while the sum is 35.

The square root of 16689401 is about 4085.2663315872. The cubic root of 16689401 is about 255.5525682561.

The spelling of 16689401 in words is "sixteen million, six hundred eighty-nine thousand, four hundred one".