1661063231 has 2 divisors, whose sum is σ = 1661063232. Its totient is φ = 1661063230.

The previous prime is 1661063219. The next prime is 1661063233. The reversal of 1661063231 is 1323601661.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (1323601661) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1661063231 is a prime.

It is a super-2 number, since 2×1661063231² = 5518262114760318722, which contains 22 as substring.

Together with 1661063233, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 1661063194 and 1661063203.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1661063233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 830531615 + 830531616.

It is an arithmetic number, because the mean of its divisors is an integer number (830531616).

Almost surely, 2^1661063231 is an apocalyptic number.

1661063231 is a deficient number, since it is larger than the sum of its proper divisors (1).

1661063231 is an equidigital number, since it uses as much as digits as its factorization.

1661063231 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3888, while the sum is 29.

The square root of 1661063231 is about 40756.1434755547. The cubic root of 1661063231 is about 1184.3008881077.

Adding to 1661063231 its reverse (1323601661), we get a palindrome (2984664892).

The spelling of 1661063231 in words is "one billion, six hundred sixty-one million, sixty-three thousand, two hundred thirty-one".