1361661401 has 2 divisors, whose sum is σ = 1361661402. Its totient is φ = 1361661400.

The previous prime is 1361661313. The next prime is 1361661403. The reversal of 1361661401 is 1041661631.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1064064400 + 297597001 = 32620^2 + 17251^2 .

It is an emirp because it is prime and its reverse (1041661631) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1361661401 - 2¹⁴ = 1361645017 is a prime.

Together with 1361661403, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (1361661403) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 680830700 + 680830701.

It is an arithmetic number, because the mean of its divisors is an integer number (680830701).

Almost surely, 2^1361661401 is an apocalyptic number.

It is an amenable number.

1361661401 is a deficient number, since it is larger than the sum of its proper divisors (1).

1361661401 is an equidigital number, since it uses as much as digits as its factorization.

1361661401 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2592, while the sum is 29.

The square root of 1361661401 is about 36900.6964839419. The cubic root of 1361661401 is about 1108.3826243190.

The spelling of 1361661401 in words is "one billion, three hundred sixty-one million, six hundred sixty-one thousand, four hundred one".