68681540 has 24 divisors (see below), whose sum is σ = 144388440. Its totient is φ = 27442688.

The previous prime is 68681531. The next prime is 68681549. The reversal of 68681540 is 4518686.

68681540 is nontrivially palindromic in base 8.

It is an interprime number because it is at equal distance from previous prime (68681531) and next prime (68681549).

It can be written as a sum of positive squares in 4 ways, for example, as 4393216 + 64288324 = 2096^2 + 8018^2 .

It is a junction number, because it is equal to n+sod(n) for n = 68681494 and 68681503.

It is not an unprimeable number, because it can be changed into a prime (68681549) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31196 + ... + 33324.

It is an arithmetic number, because the mean of its divisors is an integer number (6016185).

Almost surely, 2^68681540 is an apocalyptic number.

It is an amenable number.

68681540 is an abundant number, since it is smaller than the sum of its proper divisors (75706900).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

68681540 is a wasteful number, since it uses less digits than its factorization.

68681540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3751 (or 3749 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 38.

The square root of 68681540 is about 8287.4326543267. The cubic root of 68681540 is about 409.5246126033.

The spelling of 68681540 in words is "sixty-eight million, six hundred eighty-one thousand, five hundred forty".