68640284 has 12 divisors (see below), whose sum is σ = 120397200. Its totient is φ = 34241088.

The previous prime is 68640283. The next prime is 68640287. The reversal of 68640284 is 48204686.

It is a happy number.

It is a super-2 number, since 2×68640284² = 9422977175201312, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (68640281) 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 in 3 ways as a sum of consecutive naturals, for example, 17789 + ... + 21300.

It is an arithmetic number, because the mean of its divisors is an integer number (10033100).

Almost surely, 2^68640284 is an apocalyptic number.

It is an amenable number.

68640284 is a deficient number, since it is larger than the sum of its proper divisors (51756916).

68640284 is a wasteful number, since it uses less digits than its factorization.

68640284 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39532 (or 39530 counting only the distinct ones).

The product of its (nonzero) digits is 73728, while the sum is 38.

The square root of 68640284 is about 8284.9432104270. The cubic root of 68640284 is about 409.4425976908.

The spelling of 68640284 in words is "sixty-eight million, six hundred forty thousand, two hundred eighty-four".