228061721 has 8 divisors (see below), whose sum is σ = 243782784. Its totient is φ = 212824480.

The previous prime is 228061663. The next prime is 228061733. The reversal of 228061721 is 127160822.

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

It is a cyclic number.

It is not a de Polignac number, because 228061721 - 2¹⁸ = 227799577 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (228061741) 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, 119981 + ... + 121866.

It is an arithmetic number, because the mean of its divisors is an integer number (30472848).

Almost surely, 2^228061721 is an apocalyptic number.

It is an amenable number.

228061721 is a deficient number, since it is larger than the sum of its proper divisors (15721063).

228061721 is a wasteful number, since it uses less digits than its factorization.

228061721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 241911.

The product of its (nonzero) digits is 2688, while the sum is 29.

The square root of 228061721 is about 15101.7125187841. The cubic root of 228061721 is about 610.9665952845.

The spelling of 228061721 in words is "two hundred twenty-eight million, sixty-one thousand, seven hundred twenty-one".