139658416681 has 27 divisors (see below), whose sum is σ = 163893410487. Its totient is φ = 118660081680.

The previous prime is 139658416673. The next prime is 139658416691. The reversal of 139658416681 is 186614856931.

The square root of 139658416681 is 373709.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 136837107225 + 2821309456 = 369915^2 + 53116^2 .

It is not a de Polignac number, because 139658416681 - 2³ = 139658416673 is a prime.

It is a super-2 number, since 2×139658416681² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (139658416691) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 515344576 + ... + 515344846.

Almost surely, 2^139658416681 is an apocalyptic number.

139658416681 is the 373709-th square number.

139658416681 is the 186855-th centered octagonal number.

It is an amenable number.

139658416681 is a deficient number, since it is larger than the sum of its proper divisors (24234993806).

139658416681 is an frugal number, since it uses more digits than its factorization.

139658416681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 950 (or 475 counting only the distinct ones).

The product of its digits is 7464960, while the sum is 58.

The spelling of 139658416681 in words is "one hundred thirty-nine billion, six hundred fifty-eight million, four hundred sixteen thousand, six hundred eighty-one".