71998739 has 2 divisors, whose sum is σ = 71998740. Its totient is φ = 71998738.

The previous prime is 71998721. The next prime is 71998753. The reversal of 71998739 is 93789917.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-71998739 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (71998769) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 35999369 + 35999370.

It is an arithmetic number, because the mean of its divisors is an integer number (35999370).

Almost surely, 2^71998739 is an apocalyptic number.

71998739 is a deficient number, since it is larger than the sum of its proper divisors (1).

71998739 is an equidigital number, since it uses as much as digits as its factorization.

71998739 is an evil number, because the sum of its binary digits is even.

The product of its digits is 857304, while the sum is 53.

The square root of 71998739 is about 8485.2070687756. The cubic root of 71998739 is about 416.0143359057.

The spelling of 71998739 in words is "seventy-one million, nine hundred ninety-eight thousand, seven hundred thirty-nine".