645137351 has 2 divisors, whose sum is σ = 645137352. Its totient is φ = 645137350.

The previous prime is 645137341. The next prime is 645137357. The reversal of 645137351 is 153731546.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 645137351 - 2¹⁴ = 645120967 is a prime.

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 (645137357) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322568675 + 322568676.

It is an arithmetic number, because the mean of its divisors is an integer number (322568676).

Almost surely, 2^645137351 is an apocalyptic number.

645137351 is a deficient number, since it is larger than the sum of its proper divisors (1).

645137351 is an equidigital number, since it uses as much as digits as its factorization.

645137351 is an evil number, because the sum of its binary digits is even.

The product of its digits is 37800, while the sum is 35.

The square root of 645137351 is about 25399.5541496303. The cubic root of 645137351 is about 864.0735851072.

Adding to 645137351 its reverse (153731546), we get a palindrome (798868897).

The spelling of 645137351 in words is "six hundred forty-five million, one hundred thirty-seven thousand, three hundred fifty-one".