680696981 has 2 divisors, whose sum is σ = 680696982. Its totient is φ = 680696980.

The previous prime is 680696969. The next prime is 680696993. The reversal of 680696981 is 189696086.

It is a balanced prime because it is at equal distance from previous prime (680696969) and next prime (680696993).

It can be written as a sum of positive squares in only one way, i.e., 384512881 + 296184100 = 19609^2 + 17210^2 .

It is a cyclic number.

It is not a de Polignac number, because 680696981 - 2⁶ = 680696917 is a prime.

It is a super-2 number, since 2×680696981² = 926696759885028722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (680696921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 340348490 + 340348491.

It is an arithmetic number, because the mean of its divisors is an integer number (340348491).

Almost surely, 2^680696981 is an apocalyptic number.

It is an amenable number.

680696981 is a deficient number, since it is larger than the sum of its proper divisors (1).

680696981 is an equidigital number, since it uses as much as digits as its factorization.

680696981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1119744, while the sum is 53.

The square root of 680696981 is about 26090.1701987549. The cubic root of 680696981 is about 879.6662736793. Note that the first 3 decimals are identical.

The spelling of 680696981 in words is "six hundred eighty million, six hundred ninety-six thousand, nine hundred eighty-one".