124687681 has 4 divisors (see below), whose sum is σ = 124752852. Its totient is φ = 124622512.

The previous prime is 124687649. The next prime is 124687697. The reversal of 124687681 is 186786421.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 186786421 = 12983 ⋅14387.

It can be written as a sum of positive squares in 2 ways, for example, as 84934656 + 39753025 = 9216^2 + 6305^2 .

It is a cyclic number.

It is not a de Polignac number, because 124687681 - 2⁵ = 124687649 is a prime.

It is a super-2 number, since 2×124687681² = 31094035586315522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (124687621) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29626 + ... + 33571.

It is an arithmetic number, because the mean of its divisors is an integer number (31188213).

Almost surely, 2^124687681 is an apocalyptic number.

It is an amenable number.

124687681 is a deficient number, since it is larger than the sum of its proper divisors (65171).

124687681 is an equidigital number, since it uses as much as digits as its factorization.

124687681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65170.

The product of its digits is 129024, while the sum is 43.

The square root of 124687681 is about 11166.3638217640. The cubic root of 124687681 is about 499.5832273643.

The spelling of 124687681 in words is "one hundred twenty-four million, six hundred eighty-seven thousand, six hundred eighty-one".