640770236 has 12 divisors (see below), whose sum is σ = 1121579760. Its totient is φ = 320318880.

The previous prime is 640770203. The next prime is 640770241. The reversal of 640770236 is 632077046.

It is a junction number, because it is equal to n+sod(n) for n = 640770196 and 640770205.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 9905 + ... + 37143.

It is an arithmetic number, because the mean of its divisors is an integer number (93464980).

Almost surely, 2^640770236 is an apocalyptic number.

It is an amenable number.

640770236 is a deficient number, since it is larger than the sum of its proper divisors (480809524).

640770236 is a wasteful number, since it uses less digits than its factorization.

640770236 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33124 (or 33122 counting only the distinct ones).

The product of its (nonzero) digits is 42336, while the sum is 35.

The square root of 640770236 is about 25313.4398294661. The cubic root of 640770236 is about 862.1194505754.

The spelling of 640770236 in words is "six hundred forty million, seven hundred seventy thousand, two hundred thirty-six".