609928981 has 2 divisors, whose sum is σ = 609928982. Its totient is φ = 609928980.

The previous prime is 609928951. The next prime is 609928987. The reversal of 609928981 is 189829906.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 494172900 + 115756081 = 22230^2 + 10759^2 .

It is a cyclic number.

It is not a de Polignac number, because 609928981 - 2¹³ = 609920789 is a prime.

It is a super-2 number, since 2×609928981² = 744026723727396722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (609928987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 304964490 + 304964491.

It is an arithmetic number, because the mean of its divisors is an integer number (304964491).

Almost surely, 2^609928981 is an apocalyptic number.

It is an amenable number.

609928981 is a deficient number, since it is larger than the sum of its proper divisors (1).

609928981 is an equidigital number, since it uses as much as digits as its factorization.

609928981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 559872, while the sum is 52.

The square root of 609928981 is about 24696.7402909777. The cubic root of 609928981 is about 848.0596946266.

The spelling of 609928981 in words is "six hundred nine million, nine hundred twenty-eight thousand, nine hundred eighty-one".