813138911971 has 2 divisors, whose sum is σ = 813138911972. Its totient is φ = 813138911970.

The previous prime is 813138911953. The next prime is 813138911989. The reversal of 813138911971 is 179119831318.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (813138911953) and next prime (813138911989).

It is a cyclic number.

It is not a de Polignac number, because 813138911971 - 2⁷ = 813138911843 is a prime.

It is a super-2 number, since 2×813138911971² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (813138911471) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 406569455985 + 406569455986.

It is an arithmetic number, because the mean of its divisors is an integer number (406569455986).

Almost surely, 2^813138911971 is an apocalyptic number.

813138911971 is a deficient number, since it is larger than the sum of its proper divisors (1).

813138911971 is an equidigital number, since it uses as much as digits as its factorization.

813138911971 is an evil number, because the sum of its binary digits is even.

The product of its digits is 326592, while the sum is 52.

The spelling of 813138911971 in words is "eight hundred thirteen billion, one hundred thirty-eight million, nine hundred eleven thousand, nine hundred seventy-one".