1321061656 has 16 divisors (see below), whose sum is σ = 2537405640. Its totient is φ = 644420160.

The previous prime is 1321061633. The next prime is 1321061657. The reversal of 1321061656 is 6561601231.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1321061657) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2013486 + ... + 2014141.

Almost surely, 2^1321061656 is an apocalyptic number.

It is an amenable number.

1321061656 is a deficient number, since it is larger than the sum of its proper divisors (1216343984).

1321061656 is a wasteful number, since it uses less digits than its factorization.

1321061656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4027674 (or 4027670 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 31.

The square root of 1321061656 is about 36346.4118724256. The cubic root of 1321061656 is about 1097.2553214649.

Adding to 1321061656 its reverse (6561601231), we get a palindrome (7882662887).

The spelling of 1321061656 in words is "one billion, three hundred twenty-one million, sixty-one thousand, six hundred fifty-six".