16391000 has 64 divisors (see below), whose sum is σ = 39480480. Its totient is φ = 6364800.

The previous prime is 16390993. The next prime is 16391017. The reversal of 16391000 is 19361.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 36779 + ... + 37221.

Almost surely, 2^16391000 is an apocalyptic number.

16391000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 16391000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19740240).

16391000 is an abundant number, since it is smaller than the sum of its proper divisors (23089480).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

16391000 is a wasteful number, since it uses less digits than its factorization.

16391000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 501 (or 487 counting only the distinct ones).

The product of its (nonzero) digits is 162, while the sum is 20.

The square root of 16391000 is about 4048.5799979746. The cubic root of 16391000 is about 254.0203344127.

The spelling of 16391000 in words is "sixteen million, three hundred ninety-one thousand".