638945750 has 32 divisors (see below), whose sum is σ = 1248122304. Its totient is φ = 244464000.

The previous prime is 638945677. The next prime is 638945761. The reversal of 638945750 is 57549836.

It is a junction number, because it is equal to n+sod(n) for n = 638945695 and 638945704.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 49811 + ... + 61310.

It is an arithmetic number, because the mean of its divisors is an integer number (39003822).

Almost surely, 2^638945750 is an apocalyptic number.

638945750 is a deficient number, since it is larger than the sum of its proper divisors (609176554).

638945750 is a wasteful number, since it uses less digits than its factorization.

638945750 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111161 (or 111151 counting only the distinct ones).

The product of its (nonzero) digits is 907200, while the sum is 47.

The square root of 638945750 is about 25277.3762483372. The cubic root of 638945750 is about 861.3004257906.

The spelling of 638945750 in words is "six hundred thirty-eight million, nine hundred forty-five thousand, seven hundred fifty".