72139913971 has 2 divisors, whose sum is σ = 72139913972. Its totient is φ = 72139913970.

The previous prime is 72139913827. The next prime is 72139914019. The reversal of 72139913971 is 17931993127.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 72139913971 - 2¹³ = 72139905779 is a prime.

It is not a weakly prime, because it can be changed into another prime (72139913371) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36069956985 + 36069956986.

It is an arithmetic number, because the mean of its divisors is an integer number (36069956986).

Almost surely, 2^72139913971 is an apocalyptic number.

72139913971 is a deficient number, since it is larger than the sum of its proper divisors (1).

72139913971 is an equidigital number, since it uses as much as digits as its factorization.

72139913971 is an evil number, because the sum of its binary digits is even.

The product of its digits is 642978, while the sum is 52.

The spelling of 72139913971 in words is "seventy-two billion, one hundred thirty-nine million, nine hundred thirteen thousand, nine hundred seventy-one".