16861539 has 4 divisors (see below), whose sum is σ = 22482056. Its totient is φ = 11241024.

The previous prime is 16861519. The next prime is 16861541. The reversal of 16861539 is 93516861.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 93516861 = 3 ⋅31172287.

It is not a de Polignac number, because 16861539 - 2⁸ = 16861283 is a prime.

It is a super-2 number, since 2×16861539² = 568622994897042, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 16861497 and 16861506.

It is not an unprimeable number, because it can be changed into a prime (16861519) 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, 2810254 + ... + 2810259.

It is an arithmetic number, because the mean of its divisors is an integer number (5620514).

Almost surely, 2^16861539 is an apocalyptic number.

16861539 is a deficient number, since it is larger than the sum of its proper divisors (5620517).

16861539 is an equidigital number, since it uses as much as digits as its factorization.

16861539 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5620516.

The product of its digits is 38880, while the sum is 39.

The square root of 16861539 is about 4106.2804336772. The cubic root of 16861539 is about 256.4281724183.

The spelling of 16861539 in words is "sixteen million, eight hundred sixty-one thousand, five hundred thirty-nine".