1851315235391 has 2 divisors, whose sum is σ = 1851315235392. Its totient is φ = 1851315235390.

The previous prime is 1851315235387. The next prime is 1851315235433. The reversal of 1851315235391 is 1935325131581.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1851315235391 - 2² = 1851315235387 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1851315235381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 925657617695 + 925657617696.

It is an arithmetic number, because the mean of its divisors is an integer number (925657617696).

Almost surely, 2^{1851315235391} is an apocalyptic number.

1851315235391 is a deficient number, since it is larger than the sum of its proper divisors (1).

1851315235391 is an equidigital number, since it uses as much as digits as its factorization.

1851315235391 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 486000, while the sum is 47.

The spelling of 1851315235391 in words is "one trillion, eight hundred fifty-one billion, three hundred fifteen million, two hundred thirty-five thousand, three hundred ninety-one".