7777421853973 has 2 divisors, whose sum is σ = 7777421853974. Its totient is φ = 7777421853972.

The previous prime is 7777421853919. The next prime is 7777421853977. The reversal of 7777421853973 is 3793581247777.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4015462915044 + 3761958938929 = 2003862^2 + 1939577^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7777421853973 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7777421853977) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3888710926986 + 3888710926987.

It is an arithmetic number, because the mean of its divisors is an integer number (3888710926987).

Almost surely, 2^{7777421853973} is an apocalyptic number.

It is an amenable number.

7777421853973 is a deficient number, since it is larger than the sum of its proper divisors (1).

7777421853973 is an equidigital number, since it uses as much as digits as its factorization.

7777421853973 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 435637440, while the sum is 70.

The spelling of 7777421853973 in words is "seven trillion, seven hundred seventy-seven billion, four hundred twenty-one million, eight hundred fifty-three thousand, nine hundred seventy-three".