645351827 has 2 divisors, whose sum is σ = 645351828. Its totient is φ = 645351826.

The previous prime is 645351823. The next prime is 645351829. The reversal of 645351827 is 728153546.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 645351827 - 2² = 645351823 is a prime.

It is a super-2 number, since 2×645351827² = 832957961224475858, which contains 22 as substring.

Together with 645351829, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (645351823) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322675913 + 322675914.

It is an arithmetic number, because the mean of its divisors is an integer number (322675914).

Almost surely, 2^645351827 is an apocalyptic number.

645351827 is a deficient number, since it is larger than the sum of its proper divisors (1).

645351827 is an equidigital number, since it uses as much as digits as its factorization.

645351827 is an evil number, because the sum of its binary digits is even.

The product of its digits is 201600, while the sum is 41.

The square root of 645351827 is about 25403.7758413981. The cubic root of 645351827 is about 864.1693282916.

The spelling of 645351827 in words is "six hundred forty-five million, three hundred fifty-one thousand, eight hundred twenty-seven".