71979539 has 2 divisors, whose sum is σ = 71979540. Its totient is φ = 71979538.

The previous prime is 71979491. The next prime is 71979553. The reversal of 71979539 is 93597917.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 71979539 - 2⁸ = 71979283 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (71978539) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35989769 + 35989770.

It is an arithmetic number, because the mean of its divisors is an integer number (35989770).

Almost surely, 2^71979539 is an apocalyptic number.

71979539 is a deficient number, since it is larger than the sum of its proper divisors (1).

71979539 is an equidigital number, since it uses as much as digits as its factorization.

71979539 is an evil number, because the sum of its binary digits is even.

The product of its digits is 535815, while the sum is 50.

The square root of 71979539 is about 8484.0756125815. The cubic root of 71979539 is about 415.9773529184.

The spelling of 71979539 in words is "seventy-one million, nine hundred seventy-nine thousand, five hundred thirty-nine".