645470279 has 2 divisors, whose sum is σ = 645470280. Its totient is φ = 645470278.

The previous prime is 645470227. The next prime is 645470323. The reversal of 645470279 is 972074546.

It is an a-pointer prime, because the next prime (645470323) can be obtained adding 645470279 to its sum of digits (44).

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 645470279 - 2¹⁶ = 645404743 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (645470179) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322735139 + 322735140.

It is an arithmetic number, because the mean of its divisors is an integer number (322735140).

Almost surely, 2^645470279 is an apocalyptic number.

645470279 is a deficient number, since it is larger than the sum of its proper divisors (1).

645470279 is an equidigital number, since it uses as much as digits as its factorization.

645470279 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 423360, while the sum is 44.

The square root of 645470279 is about 25406.1071201394. The cubic root of 645470279 is about 864.2221967782. Note that the first 3 decimals are identical.

The spelling of 645470279 in words is "six hundred forty-five million, four hundred seventy thousand, two hundred seventy-nine".