71638385237 has 32 divisors (see below), whose sum is σ = 78778529280. Its totient is φ = 64874234880.

The previous prime is 71638385227. The next prime is 71638385309. The reversal of 71638385237 is 73258383617.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 71638385237 - 2³² = 67343417941 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71638385227) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 31241063 + ... + 31243355.

It is an arithmetic number, because the mean of its divisors is an integer number (2461829040).

Almost surely, 2^71638385237 is an apocalyptic number.

It is an amenable number.

71638385237 is a deficient number, since it is larger than the sum of its proper divisors (7140144043).

71638385237 is a wasteful number, since it uses less digits than its factorization.

71638385237 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2973.

The product of its digits is 5080320, while the sum is 53.

The spelling of 71638385237 in words is "seventy-one billion, six hundred thirty-eight million, three hundred eighty-five thousand, two hundred thirty-seven".