1607765231221 has 2 divisors, whose sum is σ = 1607765231222. Its totient is φ = 1607765231220.

The previous prime is 1607765231203. The next prime is 1607765231291. The reversal of 1607765231221 is 1221325677061.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1003863724900 + 603901506321 = 1001930^2 + 777111^2 .

It is a cyclic number.

It is not a de Polignac number, because 1607765231221 - 2²⁷ = 1607631013493 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1607765231291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 803882615610 + 803882615611.

It is an arithmetic number, because the mean of its divisors is an integer number (803882615611).

Almost surely, 2^{1607765231221} is an apocalyptic number.

It is an amenable number.

1607765231221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1607765231221 is an equidigital number, since it uses as much as digits as its factorization.

1607765231221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 211680, while the sum is 43.

The spelling of 1607765231221 in words is "one trillion, six hundred seven billion, seven hundred sixty-five million, two hundred thirty-one thousand, two hundred twenty-one".