640731410 has 16 divisors (see below), whose sum is σ = 1258163712. Its totient is φ = 232993200.

The previous prime is 640731391. The next prime is 640731437. The reversal of 640731410 is 14137046.

It is a self number, because there is not a number n which added to its sum of digits gives 640731410.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2912306 + ... + 2912525.

It is an arithmetic number, because the mean of its divisors is an integer number (78635232).

Almost surely, 2^640731410 is an apocalyptic number.

640731410 is a deficient number, since it is larger than the sum of its proper divisors (617432302).

640731410 is a wasteful number, since it uses less digits than its factorization.

640731410 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5824849.

The product of its (nonzero) digits is 2016, while the sum is 26.

The square root of 640731410 is about 25312.6729129897. The cubic root of 640731410 is about 862.1020375081.

Adding to 640731410 its reverse (14137046), we get a palindrome (654868456).

The spelling of 640731410 in words is "six hundred forty million, seven hundred thirty-one thousand, four hundred ten".