1301320561 has 2 divisors, whose sum is σ = 1301320562. Its totient is φ = 1301320560.

The previous prime is 1301320541. The next prime is 1301320571. The reversal of 1301320561 is 1650231031.

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., 822542400 + 478778161 = 28680^2 + 21881^2 .

It is a cyclic number.

It is not a de Polignac number, because 1301320561 - 2²³ = 1292931953 is a prime.

It is not a weakly prime, because it can be changed into another prime (1301320541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 650660280 + 650660281.

It is an arithmetic number, because the mean of its divisors is an integer number (650660281).

Almost surely, 2^1301320561 is an apocalyptic number.

It is an amenable number.

1301320561 is a deficient number, since it is larger than the sum of its proper divisors (1).

1301320561 is an equidigital number, since it uses as much as digits as its factorization.

1301320561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 540, while the sum is 22.

The square root of 1301320561 is about 36073.8209925148. The cubic root of 1301320561 is about 1091.7623095065.

Adding to 1301320561 its reverse (1650231031), we get a palindrome (2951551592).

It can be divided in two parts, 1301320 and 561, that added together give a square (1301881 = 1141²).

The spelling of 1301320561 in words is "one billion, three hundred one million, three hundred twenty thousand, five hundred sixty-one".