645832079 has 2 divisors, whose sum is σ = 645832080. Its totient is φ = 645832078.

The previous prime is 645832069. The next prime is 645832081. The reversal of 645832079 is 970238546.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-645832079 is a prime.

Together with 645832081, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (645832039) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322916039 + 322916040.

It is an arithmetic number, because the mean of its divisors is an integer number (322916040).

Almost surely, 2^645832079 is an apocalyptic number.

645832079 is a deficient number, since it is larger than the sum of its proper divisors (1).

645832079 is an equidigital number, since it uses as much as digits as its factorization.

645832079 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 362880, while the sum is 44.

The square root of 645832079 is about 25413.2264578900. The cubic root of 645832079 is about 864.3836383393.

The spelling of 645832079 in words is "six hundred forty-five million, eight hundred thirty-two thousand, seventy-nine".