638042708 has 24 divisors (see below), whose sum is σ = 1183133952. Its totient is φ = 300032384.

The previous prime is 638042681. The next prime is 638042723. The reversal of 638042708 is 807240836.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 121391 + ... + 126537.

It is an arithmetic number, because the mean of its divisors is an integer number (49297248).

Almost surely, 2^638042708 is an apocalyptic number.

638042708 is a gapful number since it is divisible by the number (68) formed by its first and last digit.

It is an amenable number.

638042708 is a deficient number, since it is larger than the sum of its proper divisors (545091244).

638042708 is a wasteful number, since it uses less digits than its factorization.

638042708 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6991 (or 6989 counting only the distinct ones).

The product of its (nonzero) digits is 64512, while the sum is 38.

The square root of 638042708 is about 25259.5072794384. The cubic root of 638042708 is about 860.8944668745.

The spelling of 638042708 in words is "six hundred thirty-eight million, forty-two thousand, seven hundred eight".