612528221 has 2 divisors, whose sum is σ = 612528222. Its totient is φ = 612528220.

The previous prime is 612528199. The next prime is 612528253. The reversal of 612528221 is 122825216.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 501984025 + 110544196 = 22405^2 + 10514^2 .

It is a cyclic number.

It is not a de Polignac number, because 612528221 - 2¹⁰ = 612527197 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (612522221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 306264110 + 306264111.

It is an arithmetic number, because the mean of its divisors is an integer number (306264111).

Almost surely, 2^612528221 is an apocalyptic number.

It is an amenable number.

612528221 is a deficient number, since it is larger than the sum of its proper divisors (1).

612528221 is an equidigital number, since it uses as much as digits as its factorization.

612528221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3840, while the sum is 29.

The square root of 612528221 is about 24749.3074852611. The cubic root of 612528221 is about 849.2626690083.

The spelling of 612528221 in words is "six hundred twelve million, five hundred twenty-eight thousand, two hundred twenty-one".