645154228919 has 2 divisors, whose sum is σ = 645154228920. Its totient is φ = 645154228918.

The previous prime is 645154228907. The next prime is 645154228931. The reversal of 645154228919 is 919822451546.

It is a balanced prime because it is at equal distance from previous prime (645154228907) and next prime (645154228931).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-645154228919 is a prime.

It is a super-2 number, since 2×645154228919² (a number of 24 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (645154228219) 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, 322577114459 + 322577114460.

It is an arithmetic number, because the mean of its divisors is an integer number (322577114460).

Almost surely, 2^645154228919 is an apocalyptic number.

645154228919 is a deficient number, since it is larger than the sum of its proper divisors (1).

645154228919 is an equidigital number, since it uses as much as digits as its factorization.

645154228919 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6220800, while the sum is 56.

The spelling of 645154228919 in words is "six hundred forty-five billion, one hundred fifty-four million, two hundred twenty-eight thousand, nine hundred nineteen".