1561967653 has 2 divisors, whose sum is σ = 1561967654. Its totient is φ = 1561967652.

The previous prime is 1561967629. The next prime is 1561967669. The reversal of 1561967653 is 3567691651.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1459087204 + 102880449 = 38198^2 + 10143^2 .

It is a cyclic number.

It is not a de Polignac number, because 1561967653 - 2¹³ = 1561959461 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1561967597 and 1561967606.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1561967153) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 780983826 + 780983827.

It is an arithmetic number, because the mean of its divisors is an integer number (780983827).

Almost surely, 2^1561967653 is an apocalyptic number.

It is an amenable number.

1561967653 is a deficient number, since it is larger than the sum of its proper divisors (1).

1561967653 is an equidigital number, since it uses as much as digits as its factorization.

1561967653 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1020600, while the sum is 49.

The square root of 1561967653 is about 39521.7364623570. The cubic root of 1561967653 is about 1160.2654101866.

The spelling of 1561967653 in words is "one billion, five hundred sixty-one million, nine hundred sixty-seven thousand, six hundred fifty-three".