1641520356449 has 2 divisors, whose sum is σ = 1641520356450. Its totient is φ = 1641520356448.

The previous prime is 1641520356367. The next prime is 1641520356529. The reversal of 1641520356449 is 9446530251461.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1639180893025 + 2339463424 = 1280305^2 + 48368^2 .

It is a cyclic number.

It is not a de Polignac number, because 1641520356449 - 2²⁰ = 1641519307873 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1641520356397 and 1641520356406.

It is not a weakly prime, because it can be changed into another prime (1641510356449) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 820760178224 + 820760178225.

It is an arithmetic number, because the mean of its divisors is an integer number (820760178225).

Almost surely, 2^{1641520356449} is an apocalyptic number.

It is an amenable number.

1641520356449 is a deficient number, since it is larger than the sum of its proper divisors (1).

1641520356449 is an equidigital number, since it uses as much as digits as its factorization.

1641520356449 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3110400, while the sum is 50.

The spelling of 1641520356449 in words is "one trillion, six hundred forty-one billion, five hundred twenty million, three hundred fifty-six thousand, four hundred forty-nine".