641999078 has 12 divisors (see below), whose sum is σ = 1120223052. Its totient is φ = 275142420.

The previous prime is 641999077. The next prime is 641999081. The reversal of 641999078 is 870999146.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (641999077) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 3275408 + ... + 3275603.

It is an arithmetic number, because the mean of its divisors is an integer number (93351921).

Almost surely, 2^641999078 is an apocalyptic number.

641999078 is a deficient number, since it is larger than the sum of its proper divisors (478223974).

641999078 is a wasteful number, since it uses less digits than its factorization.

641999078 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6551027 (or 6551020 counting only the distinct ones).

The product of its (nonzero) digits is 979776, while the sum is 53.

The square root of 641999078 is about 25337.7007244146. The cubic root of 641999078 is about 862.6702106978.

The spelling of 641999078 in words is "six hundred forty-one million, nine hundred ninety-nine thousand, seventy-eight".