216257428 has 6 divisors (see below), whose sum is σ = 378450506. Its totient is φ = 108128712.

The previous prime is 216257423. The next prime is 216257429. The reversal of 216257428 is 824752612.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 184199184 + 32058244 = 13572^2 + 5662^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216257423) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 27032175 + ... + 27032182.

Almost surely, 2^216257428 is an apocalyptic number.

It is an amenable number.

216257428 is a deficient number, since it is larger than the sum of its proper divisors (162193078).

216257428 is a wasteful number, since it uses less digits than its factorization.

216257428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54064361 (or 54064359 counting only the distinct ones).

The product of its digits is 53760, while the sum is 37.

The square root of 216257428 is about 14705.6937272609. The cubic root of 216257428 is about 600.2382646300.

The spelling of 216257428 in words is "two hundred sixteen million, two hundred fifty-seven thousand, four hundred twenty-eight".