640197963 has 12 divisors (see below), whose sum is σ = 934264968. Its totient is φ = 422398080.

The previous prime is 640197953. The next prime is 640197973. The reversal of 640197963 is 369791046.

It is an interprime number because it is at equal distance from previous prime (640197953) and next prime (640197973).

It is not a de Polignac number, because 640197963 - 2⁹ = 640197451 is a prime.

It is not an unprimeable number, because it can be changed into a prime (640197923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 365793 + ... + 367538.

It is an arithmetic number, because the mean of its divisors is an integer number (77855414).

Almost surely, 2^640197963 is an apocalyptic number.

640197963 is a deficient number, since it is larger than the sum of its proper divisors (294067005).

640197963 is a wasteful number, since it uses less digits than its factorization.

640197963 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 733434 (or 733431 counting only the distinct ones).

The product of its (nonzero) digits is 244944, while the sum is 45.

The square root of 640197963 is about 25302.1335661639. The cubic root of 640197963 is about 861.8627206769.

The spelling of 640197963 in words is "six hundred forty million, one hundred ninety-seven thousand, nine hundred sixty-three".