645201277 has 12 divisors (see below), whose sum is σ = 764704476. Its totient is φ = 542592960.

The previous prime is 645201241. The next prime is 645201307. The reversal of 645201277 is 772102546.

It can be written as a sum of positive squares in 2 ways, for example, as 227979801 + 417221476 = 15099^2 + 20426^2 .

It is a de Polignac number, because none of the positive numbers 2^k-645201277 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645201377) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 121624 + ... + 126817.

It is an arithmetic number, because the mean of its divisors is an integer number (63725373).

Almost surely, 2^645201277 is an apocalyptic number.

It is an amenable number.

645201277 is a deficient number, since it is larger than the sum of its proper divisors (119503199).

645201277 is a wasteful number, since it uses less digits than its factorization.

645201277 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 248508 (or 248501 counting only the distinct ones).

The product of its (nonzero) digits is 23520, while the sum is 34.

The square root of 645201277 is about 25400.8125263740. The cubic root of 645201277 is about 864.1021242204.

The spelling of 645201277 in words is "six hundred forty-five million, two hundred one thousand, two hundred seventy-seven".