16200991 has 4 divisors (see below), whose sum is σ = 16213000. Its totient is φ = 16188984.

The previous prime is 16200979. The next prime is 16201007. The reversal of 16200991 is 19900261.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 16200991 - 2⁵ = 16200959 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16200911) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3681 + ... + 6778.

It is an arithmetic number, because the mean of its divisors is an integer number (4053250).

Almost surely, 2^16200991 is an apocalyptic number.

16200991 is a deficient number, since it is larger than the sum of its proper divisors (12009).

16200991 is a wasteful number, since it uses less digits than its factorization.

16200991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12008.

The product of its (nonzero) digits is 972, while the sum is 28.

The square root of 16200991 is about 4025.0454655817. The cubic root of 16200991 is about 253.0349590024.

The spelling of 16200991 in words is "sixteen million, two hundred thousand, nine hundred ninety-one".