7905819521 has 2 divisors, whose sum is σ = 7905819522. Its totient is φ = 7905819520.

The previous prime is 7905819511. The next prime is 7905819527. The reversal of 7905819521 is 1259185097.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4140279025 + 3765540496 = 64345^2 + 61364^2 .

It is an emirp because it is prime and its reverse (1259185097) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7905819521 - 2⁶ = 7905819457 is a prime.

It is not a weakly prime, because it can be changed into another prime (7905819527) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3952909760 + 3952909761.

It is an arithmetic number, because the mean of its divisors is an integer number (3952909761).

Almost surely, 2^7905819521 is an apocalyptic number.

It is an amenable number.

7905819521 is a deficient number, since it is larger than the sum of its proper divisors (1).

7905819521 is an equidigital number, since it uses as much as digits as its factorization.

7905819521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 226800, while the sum is 47.

The square root of 7905819521 is about 88914.6755097267. The cubic root of 7905819521 is about 1992.1206252423.

The spelling of 7905819521 in words is "seven billion, nine hundred five million, eight hundred nineteen thousand, five hundred twenty-one".