71987747 has 12 divisors (see below), whose sum is σ = 79240464. Its totient is φ = 65351520.

The previous prime is 71987731. The next prime is 71987749. The reversal of 71987747 is 74778917.

It is not a de Polignac number, because 71987747 - 2⁴ = 71987731 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 71987695 and 71987704.

It is not an unprimeable number, because it can be changed into a prime (71987749) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 6818 + ... + 13800.

It is an arithmetic number, because the mean of its divisors is an integer number (6603372).

Almost surely, 2^71987747 is an apocalyptic number.

71987747 is a deficient number, since it is larger than the sum of its proper divisors (7252717).

71987747 is a wasteful number, since it uses less digits than its factorization.

71987747 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7070 (or 7057 counting only the distinct ones).

The product of its digits is 691488, while the sum is 50.

The square root of 71987747 is about 8484.5593285686. The cubic root of 71987747 is about 415.9931639502.

The spelling of 71987747 in words is "seventy-one million, nine hundred eighty-seven thousand, seven hundred forty-seven".