645501047 has 2 divisors, whose sum is σ = 645501048. Its totient is φ = 645501046.

The previous prime is 645501023. The next prime is 645501061. The reversal of 645501047 is 740105546.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 645501047 - 2¹⁸ = 645238903 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (645501097) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 322750523 + 322750524.

It is an arithmetic number, because the mean of its divisors is an integer number (322750524).

Almost surely, 2^645501047 is an apocalyptic number.

645501047 is a deficient number, since it is larger than the sum of its proper divisors (1).

645501047 is an equidigital number, since it uses as much as digits as its factorization.

645501047 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16800, while the sum is 32.

The square root of 645501047 is about 25406.7126366242. The cubic root of 645501047 is about 864.2359283508.

The spelling of 645501047 in words is "six hundred forty-five million, five hundred one thousand, forty-seven".