16261891 has 4 divisors (see below), whose sum is σ = 17117800. Its totient is φ = 15405984.

The previous prime is 16261873. The next prime is 16261901. The reversal of 16261891 is 19816261.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19816261 = 263 ⋅75347.

It is a cyclic number.

It is not a de Polignac number, because 16261891 - 2¹¹ = 16259843 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16261801) 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, 427926 + ... + 427963.

It is an arithmetic number, because the mean of its divisors is an integer number (4279450).

Almost surely, 2^16261891 is an apocalyptic number.

16261891 is a deficient number, since it is larger than the sum of its proper divisors (855909).

16261891 is an equidigital number, since it uses as much as digits as its factorization.

16261891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 855908.

The product of its digits is 5184, while the sum is 34.

The square root of 16261891 is about 4032.6035014616. The cubic root of 16261891 is about 253.3516178323.

The spelling of 16261891 in words is "sixteen million, two hundred sixty-one thousand, eight hundred ninety-one".