16791281 has 4 divisors (see below), whose sum is σ = 18082932. Its totient is φ = 15499632.

The previous prime is 16791251. The next prime is 16791289. The reversal of 16791281 is 18219761.

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

It can be written as a sum of positive squares in 2 ways, for example, as 3534400 + 13256881 = 1880^2 + 3641^2 .

It is a cyclic number.

It is not a de Polignac number, because 16791281 - 2¹⁴ = 16774897 is a prime.

It is a super-2 number, since 2×16791281² = 563894235241922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16791289) 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, 645806 + ... + 645831.

It is an arithmetic number, because the mean of its divisors is an integer number (4520733).

Almost surely, 2^16791281 is an apocalyptic number.

It is an amenable number.

16791281 is a deficient number, since it is larger than the sum of its proper divisors (1291651).

16791281 is a wasteful number, since it uses less digits than its factorization.

16791281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1291650.

The product of its digits is 6048, while the sum is 35.

The square root of 16791281 is about 4097.7165592559. The cubic root of 16791281 is about 256.0715183076.

The spelling of 16791281 in words is "sixteen million, seven hundred ninety-one thousand, two hundred eighty-one".