783420672721 has 2 divisors, whose sum is σ = 783420672722. Its totient is φ = 783420672720.

The previous prime is 783420672679. The next prime is 783420672773. The reversal of 783420672721 is 127276024387.

783420672721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 407185648321 + 376235024400 = 638111^2 + 613380^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-783420672721 is a prime.

It is a super-2 number, since 2×783420672721² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (783420675721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 391710336360 + 391710336361.

It is an arithmetic number, because the mean of its divisors is an integer number (391710336361).

Almost surely, 2^783420672721 is an apocalyptic number.

It is an amenable number.

783420672721 is a deficient number, since it is larger than the sum of its proper divisors (1).

783420672721 is an equidigital number, since it uses as much as digits as its factorization.

783420672721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1580544, while the sum is 49.

The spelling of 783420672721 in words is "seven hundred eighty-three billion, four hundred twenty million, six hundred seventy-two thousand, seven hundred twenty-one".