18875261 has 4 divisors (see below), whose sum is σ = 19231452. Its totient is φ = 18519072.

The previous prime is 18875243. The next prime is 18875267. The reversal of 18875261 is 16257881.

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 15452761 + 3422500 = 3931^2 + 1850^2 .

It is a cyclic number.

It is not a de Polignac number, because 18875261 - 2¹⁴ = 18858877 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 (18875267) 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, 178016 + ... + 178121.

It is an arithmetic number, because the mean of its divisors is an integer number (4807863).

Almost surely, 2^18875261 is an apocalyptic number.

It is an amenable number.

18875261 is a deficient number, since it is larger than the sum of its proper divisors (356191).

18875261 is an equidigital number, since it uses as much as digits as its factorization.

18875261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 356190.

The product of its digits is 26880, while the sum is 38.

The square root of 18875261 is about 4344.5668368665. The cubic root of 18875261 is about 266.2549283107.

The spelling of 18875261 in words is "eighteen million, eight hundred seventy-five thousand, two hundred sixty-one".