638661060 has 72 divisors (see below), whose sum is σ = 2039244480. Its totient is φ = 161345088.

The previous prime is 638661031. The next prime is 638661109. The reversal of 638661060 is 60166836.

638661060 is a `hidden beast` number, since 6 + 38 + 6 + 610 + 6 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

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 23 ways as a sum of consecutive naturals, for example, 89952 + ... + 96791.

It is an arithmetic number, because the mean of its divisors is an integer number (28322840).

Almost surely, 2^638661060 is an apocalyptic number.

638661060 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

638661060 is an abundant number, since it is smaller than the sum of its proper divisors (1400583420).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

638661060 is a wasteful number, since it uses less digits than its factorization.

638661060 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 186777 (or 186772 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 36.

The square root of 638661060 is about 25271.7443007007. The cubic root of 638661060 is about 861.1724858494.

The spelling of 638661060 in words is "six hundred thirty-eight million, six hundred sixty-one thousand, sixty".