228321261 has 40 divisors (see below), whose sum is σ = 392736960. Its totient is φ = 129485952.

The previous prime is 228321239. The next prime is 228321283. The reversal of 228321261 is 162123822.

It is an interprime number because it is at equal distance from previous prime (228321239) and next prime (228321283).

It is not a de Polignac number, because 228321261 - 2¹¹ = 228319213 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (228321221) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 77365 + ... + 80261.

It is an arithmetic number, because the mean of its divisors is an integer number (9818424).

Almost surely, 2^228321261 is an apocalyptic number.

228321261 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

228321261 is a deficient number, since it is larger than the sum of its proper divisors (164415699).

228321261 is a wasteful number, since it uses less digits than its factorization.

228321261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3055 (or 3046 counting only the distinct ones).

The product of its digits is 2304, while the sum is 27.

The square root of 228321261 is about 15110.3031405727. The cubic root of 228321261 is about 611.1982725619.

It can be divided in two parts, 228 and 321261, that added together give a square (321489 = 567²).

The spelling of 228321261 in words is "two hundred twenty-eight million, three hundred twenty-one thousand, two hundred sixty-one".