659227981 has 2 divisors, whose sum is σ = 659227982. Its totient is φ = 659227980.

The previous prime is 659227973. The next prime is 659227997. The reversal of 659227981 is 189722956.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 631717956 + 27510025 = 25134^2 + 5245^2 .

It is a cyclic number.

It is not a de Polignac number, because 659227981 - 2³ = 659227973 is a prime.

It is a super-4 number, since 4×659227981⁴ (a number of 36 digits) contains 4444 as substring. Note that it is a super-d number also for d = 2.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (659227931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 329613990 + 329613991.

It is an arithmetic number, because the mean of its divisors is an integer number (329613991).

Almost surely, 2^659227981 is an apocalyptic number.

It is an amenable number.

659227981 is a deficient number, since it is larger than the sum of its proper divisors (1).

659227981 is an equidigital number, since it uses as much as digits as its factorization.

659227981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 544320, while the sum is 49.

The square root of 659227981 is about 25675.4353614501. The cubic root of 659227981 is about 870.3191593367.

The spelling of 659227981 in words is "six hundred fifty-nine million, two hundred twenty-seven thousand, nine hundred eighty-one".