7425205257721 has 2 divisors, whose sum is σ = 7425205257722. Its totient is φ = 7425205257720.

The previous prime is 7425205257641. The next prime is 7425205257793. The reversal of 7425205257721 is 1277525025247.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5728076355600 + 1697128902121 = 2393340^2 + 1302739^2 .

It is an emirp because it is prime and its reverse (1277525025247) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7425205257721 - 2¹⁷ = 7425205126649 is a prime.

It is a super-2 number, since 2×7425205257721² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (7425205257521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3712602628860 + 3712602628861.

It is an arithmetic number, because the mean of its divisors is an integer number (3712602628861).

Almost surely, 2^{7425205257721} is an apocalyptic number.

It is an amenable number.

7425205257721 is a deficient number, since it is larger than the sum of its proper divisors (1).

7425205257721 is an equidigital number, since it uses as much as digits as its factorization.

7425205257721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2744000, while the sum is 49.

The spelling of 7425205257721 in words is "seven trillion, four hundred twenty-five billion, two hundred five million, two hundred fifty-seven thousand, seven hundred twenty-one".