1321797823 has 2 divisors, whose sum is σ = 1321797824. Its totient is φ = 1321797822.

The previous prime is 1321797803. The next prime is 1321797853. The reversal of 1321797823 is 3287971231.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1321797823 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1321797823.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1321797803) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 660898911 + 660898912.

It is an arithmetic number, because the mean of its divisors is an integer number (660898912).

Almost surely, 2^1321797823 is an apocalyptic number.

1321797823 is a deficient number, since it is larger than the sum of its proper divisors (1).

1321797823 is an equidigital number, since it uses as much as digits as its factorization.

1321797823 is an evil number, because the sum of its binary digits is even.

The product of its digits is 127008, while the sum is 43.

The square root of 1321797823 is about 36356.5375551633. The cubic root of 1321797823 is about 1097.4591002862.

The spelling of 1321797823 in words is "one billion, three hundred twenty-one million, seven hundred ninety-seven thousand, eight hundred twenty-three".