1361217961 has 2 divisors, whose sum is σ = 1361217962. Its totient is φ = 1361217960.

The previous prime is 1361217943. The next prime is 1361217983. The reversal of 1361217961 is 1697121631.

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., 1294632361 + 66585600 = 35981^2 + 8160^2 .

It is a cyclic number.

It is not a de Polignac number, because 1361217961 - 2¹¹ = 1361215913 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1361217961.

It is not a weakly prime, because it can be changed into another prime (1361217911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 680608980 + 680608981.

It is an arithmetic number, because the mean of its divisors is an integer number (680608981).

Almost surely, 2^1361217961 is an apocalyptic number.

It is an amenable number.

1361217961 is a deficient number, since it is larger than the sum of its proper divisors (1).

1361217961 is an equidigital number, since it uses as much as digits as its factorization.

1361217961 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13608, while the sum is 37.

The square root of 1361217961 is about 36894.6874359982. The cubic root of 1361217961 is about 1108.2622922613.

The spelling of 1361217961 in words is "one billion, three hundred sixty-one million, two hundred seventeen thousand, nine hundred sixty-one".