7661753521 has 2 divisors, whose sum is σ = 7661753522. Its totient is φ = 7661753520.

The previous prime is 7661753479. The next prime is 7661753543. The reversal of 7661753521 is 1253571667.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6804435121 + 857318400 = 82489^2 + 29280^2 .

It is a cyclic number.

It is not a de Polignac number, because 7661753521 - 2⁹ = 7661753009 is a prime.

It is not a weakly prime, because it can be changed into another prime (7661753221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3830876760 + 3830876761.

It is an arithmetic number, because the mean of its divisors is an integer number (3830876761).

Almost surely, 2^7661753521 is an apocalyptic number.

It is an amenable number.

7661753521 is a deficient number, since it is larger than the sum of its proper divisors (1).

7661753521 is an equidigital number, since it uses as much as digits as its factorization.

7661753521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 264600, while the sum is 43.

The square root of 7661753521 is about 87531.4430419149. The cubic root of 7661753521 is about 1971.4059312927.

The spelling of 7661753521 in words is "seven billion, six hundred sixty-one million, seven hundred fifty-three thousand, five hundred twenty-one".