638613970 has 16 divisors (see below), whose sum is σ = 1153880640. Its totient is φ = 254473264.

The previous prime is 638613967. The next prime is 638613977. The reversal of 638613970 is 79316836.

It is a super-3 number, since 3×638613970³ (a number of 27 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (638613977) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 118780 + ... + 124039.

It is an arithmetic number, because the mean of its divisors is an integer number (72117540).

Almost surely, 2^638613970 is an apocalyptic number.

638613970 is a deficient number, since it is larger than the sum of its proper divisors (515266670).

638613970 is a wasteful number, since it uses less digits than its factorization.

638613970 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 243089.

The product of its (nonzero) digits is 163296, while the sum is 43.

The square root of 638613970 is about 25270.8126105988. The cubic root of 638613970 is about 861.1513198968.

The spelling of 638613970 in words is "six hundred thirty-eight million, six hundred thirteen thousand, nine hundred seventy".