78261031050491 has 2 divisors, whose sum is σ = 78261031050492. Its totient is φ = 78261031050490.

The previous prime is 78261031050467. The next prime is 78261031050493. The reversal of 78261031050491 is 19405013016287.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 78261031050491 - 2³⁰ = 78259957308667 is a prime.

It is a super-2 number, since 2×78261031050491² (a number of 29 digits) contains 22 as substring.

It is a Sophie Germain prime.

Together with 78261031050493, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (78261031050493) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39130515525245 + 39130515525246.

It is an arithmetic number, because the mean of its divisors is an integer number (39130515525246).

It is a 1-persistent number, because it is pandigital, but 2⋅78261031050491 = 156522062100982 is not.

Almost surely, 2^{78261031050491} is an apocalyptic number.

78261031050491 is a deficient number, since it is larger than the sum of its proper divisors (1).

78261031050491 is an equidigital number, since it uses as much as digits as its factorization.

78261031050491 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 362880, while the sum is 47.

The spelling of 78261031050491 in words is "seventy-eight trillion, two hundred sixty-one billion, thirty-one million, fifty thousand, four hundred ninety-one".