656128001 has 2 divisors, whose sum is σ = 656128002. Its totient is φ = 656128000.

The previous prime is 656127917. The next prime is 656128009. The reversal of 656128001 is 100821656.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 555827776 + 100300225 = 23576^2 + 10015^2 .

It is a cyclic number.

It is not a de Polignac number, because 656128001 - 2¹⁸ = 655865857 is a prime.

It is a super-3 number, since 3×656128001³ (a number of 27 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (656128009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 328064000 + 328064001.

It is an arithmetic number, because the mean of its divisors is an integer number (328064001).

Almost surely, 2^656128001 is an apocalyptic number.

It is an amenable number.

656128001 is a deficient number, since it is larger than the sum of its proper divisors (1).

656128001 is an equidigital number, since it uses as much as digits as its factorization.

656128001 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2880, while the sum is 29.

The square root of 656128001 is about 25614.9956275616. The cubic root of 656128001 is about 868.9528075002.

Adding to 656128001 its reverse (100821656), we get a palindrome (756949657).

The spelling of 656128001 in words is "six hundred fifty-six million, one hundred twenty-eight thousand, one".