645829501 has 2 divisors, whose sum is σ = 645829502. Its totient is φ = 645829500.

The previous prime is 645829463. The next prime is 645829519. The reversal of 645829501 is 105928546.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 611325625 + 34503876 = 24725^2 + 5874^2 .

It is a cyclic number.

It is not a de Polignac number, because 645829501 - 2²³ = 637440893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (645829001) 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, 322914750 + 322914751.

It is an arithmetic number, because the mean of its divisors is an integer number (322914751).

Almost surely, 2^645829501 is an apocalyptic number.

It is an amenable number.

645829501 is a deficient number, since it is larger than the sum of its proper divisors (1).

645829501 is an equidigital number, since it uses as much as digits as its factorization.

645829501 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 86400, while the sum is 40.

The square root of 645829501 is about 25413.1757362200. The cubic root of 645829501 is about 864.3824882034.

The spelling of 645829501 in words is "six hundred forty-five million, eight hundred twenty-nine thousand, five hundred one".