71638730 has 8 divisors (see below), whose sum is σ = 128949732. Its totient is φ = 28655488.

The previous prime is 71638717. The next prime is 71638733. The reversal of 71638730 is 3783617.

It can be written as a sum of positive squares in 2 ways, for example, as 57896881 + 13741849 = 7609^2 + 3707^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (71638733) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3581927 + ... + 3581946.

Almost surely, 2^71638730 is an apocalyptic number.

71638730 is a deficient number, since it is larger than the sum of its proper divisors (57311002).

71638730 is a wasteful number, since it uses less digits than its factorization.

71638730 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7163880.

The product of its (nonzero) digits is 21168, while the sum is 35.

The square root of 71638730 is about 8463.9665642062. The cubic root of 71638730 is about 415.3197902866.

The spelling of 71638730 in words is "seventy-one million, six hundred thirty-eight thousand, seven hundred thirty".