16381001 has 24 divisors (see below), whose sum is σ = 20695104. Its totient is φ = 12692160.

The previous prime is 16380971. The next prime is 16381003. The reversal of 16381001 is 10018361.

It is a de Polignac number, because none of the positive numbers 2^k-16381001 is a prime.

It is not an unprimeable number, because it can be changed into a prime (16381003) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 72050 + ... + 72276.

It is an arithmetic number, because the mean of its divisors is an integer number (862296).

Almost surely, 2^16381001 is an apocalyptic number.

It is an amenable number.

16381001 is a deficient number, since it is larger than the sum of its proper divisors (4314103).

16381001 is a wasteful number, since it uses less digits than its factorization.

16381001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 321 (or 308 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 20.

The square root of 16381001 is about 4047.3449321747. The cubic root of 16381001 is about 253.9686705732.

Adding to 16381001 its reverse (10018361), we get a palindrome (26399362).

The spelling of 16381001 in words is "sixteen million, three hundred eighty-one thousand, one".