645061093 has 2 divisors, whose sum is σ = 645061094. Its totient is φ = 645061092.

The previous prime is 645061091. The next prime is 645061099. The reversal of 645061093 is 390160546.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 360734049 + 284327044 = 18993^2 + 16862^2 .

It is a cyclic number.

It is not a de Polignac number, because 645061093 - 2¹ = 645061091 is a prime.

It is a super-2 number, since 2×645061093² = 832207627404709298, which contains 22 as substring.

Together with 645061091, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (645061091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322530546 + 322530547.

It is an arithmetic number, because the mean of its divisors is an integer number (322530547).

Almost surely, 2^645061093 is an apocalyptic number.

It is an amenable number.

645061093 is a deficient number, since it is larger than the sum of its proper divisors (1).

645061093 is an equidigital number, since it uses as much as digits as its factorization.

645061093 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 19440, while the sum is 34.

The square root of 645061093 is about 25398.0529371840. The cubic root of 645061093 is about 864.0395380319.

The spelling of 645061093 in words is "six hundred forty-five million, sixty-one thousand, ninety-three".