1813720847 has 2 divisors, whose sum is σ = 1813720848. Its totient is φ = 1813720846.

The previous prime is 1813720823. The next prime is 1813720859. The reversal of 1813720847 is 7480273181.

It is a strong prime.

It is an emirp because it is prime and its reverse (7480273181) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1813720847 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1813720247) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 906860423 + 906860424.

It is an arithmetic number, because the mean of its divisors is an integer number (906860424).

Almost surely, 2^1813720847 is an apocalyptic number.

1813720847 is a deficient number, since it is larger than the sum of its proper divisors (1).

1813720847 is an equidigital number, since it uses as much as digits as its factorization.

1813720847 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 75264, while the sum is 41.

The square root of 1813720847 is about 42587.8016220607. The cubic root of 1813720847 is about 1219.5234291521.

The spelling of 1813720847 in words is "one billion, eight hundred thirteen million, seven hundred twenty thousand, eight hundred forty-seven".