16686401 has 8 divisors (see below), whose sum is σ = 18238464. Its totient is φ = 15197760.

The previous prime is 16686391. The next prime is 16686407. The reversal of 16686401 is 10468661.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 16686401 - 2⁶ = 16686337 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (16686407) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15305 + ... + 16358.

It is an arithmetic number, because the mean of its divisors is an integer number (2279808).

Almost surely, 2^16686401 is an apocalyptic number.

It is an amenable number.

16686401 is a deficient number, since it is larger than the sum of its proper divisors (1552063).

16686401 is a wasteful number, since it uses less digits than its factorization.

16686401 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31711.

The product of its (nonzero) digits is 6912, while the sum is 32.

The square root of 16686401 is about 4084.8991419618. The cubic root of 16686401 is about 255.5372550712.

The spelling of 16686401 in words is "sixteen million, six hundred eighty-six thousand, four hundred one".