139759681 has 2 divisors, whose sum is σ = 139759682. Its totient is φ = 139759680.

The previous prime is 139759679. The next prime is 139759727. The reversal of 139759681 is 186957931.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 118461456 + 21298225 = 10884^2 + 4615^2 .

It is a cyclic number.

It is not a de Polignac number, because 139759681 - 2¹ = 139759679 is a prime.

It is a super-2 number, since 2×139759681² = 39065536866443522, which contains 22 as substring.

Together with 139759679, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (139759621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69879840 + 69879841.

It is an arithmetic number, because the mean of its divisors is an integer number (69879841).

Almost surely, 2^139759681 is an apocalyptic number.

It is an amenable number.

139759681 is a deficient number, since it is larger than the sum of its proper divisors (1).

139759681 is an equidigital number, since it uses as much as digits as its factorization.

139759681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 408240, while the sum is 49.

The square root of 139759681 is about 11821.9998731179. Note that the first 3 decimals coincide. The cubic root of 139759681 is about 518.9521316900.

The spelling of 139759681 in words is "one hundred thirty-nine million, seven hundred fifty-nine thousand, six hundred eighty-one".