81850293139 has 2 divisors, whose sum is σ = 81850293140. Its totient is φ = 81850293138.

The previous prime is 81850293089. The next prime is 81850293149. The reversal of 81850293139 is 93139205818.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81850293139 - 2⁷ = 81850293011 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 81850293092 and 81850293101.

It is not a weakly prime, because it can be changed into another prime (81850293149) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40925146569 + 40925146570.

It is an arithmetic number, because the mean of its divisors is an integer number (40925146570).

Almost surely, 2^81850293139 is an apocalyptic number.

81850293139 is a deficient number, since it is larger than the sum of its proper divisors (1).

81850293139 is an equidigital number, since it uses as much as digits as its factorization.

81850293139 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 466560, while the sum is 49.

The spelling of 81850293139 in words is "eighty-one billion, eight hundred fifty million, two hundred ninety-three thousand, one hundred thirty-nine".