228781861 has 8 divisors (see below), whose sum is σ = 285234624. Its totient is φ = 178271520.

The previous prime is 228781843. The next prime is 228781909. The reversal of 228781861 is 168187822.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 228781861 - 2¹⁹ = 228257573 is a prime.

It is a super-2 number, since 2×228781861² = 104682279845246642, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (228781361) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1485520 + ... + 1485673.

It is an arithmetic number, because the mean of its divisors is an integer number (35654328).

Almost surely, 2^228781861 is an apocalyptic number.

It is an amenable number.

228781861 is a deficient number, since it is larger than the sum of its proper divisors (56452763).

228781861 is a wasteful number, since it uses less digits than its factorization.

228781861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2971211.

The product of its digits is 86016, while the sum is 43.

The square root of 228781861 is about 15125.5367177499. The cubic root of 228781861 is about 611.6089933009.

It can be divided in two parts, 2287 and 81861, that added together give a palindrome (84148).

The spelling of 228781861 in words is "two hundred twenty-eight million, seven hundred eighty-one thousand, eight hundred sixty-one".