228315621 has 4 divisors (see below), whose sum is σ = 304420832. Its totient is φ = 152210412.

The previous prime is 228315611. The next prime is 228315631. The reversal of 228315621 is 126513822.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (228315611) and next prime (228315631).

It is not a de Polignac number, because 228315621 - 2¹¹ = 228313573 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (228315611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 38052601 + ... + 38052606.

It is an arithmetic number, because the mean of its divisors is an integer number (76105208).

Almost surely, 2^228315621 is an apocalyptic number.

It is an amenable number.

228315621 is a deficient number, since it is larger than the sum of its proper divisors (76105211).

228315621 is an equidigital number, since it uses as much as digits as its factorization.

228315621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76105210.

The product of its digits is 5760, while the sum is 30.

The square root of 228315621 is about 15110.1165117943. The cubic root of 228315621 is about 611.1932399066.

The spelling of 228315621 in words is "two hundred twenty-eight million, three hundred fifteen thousand, six hundred twenty-one".