67656978440 has 16 divisors (see below), whose sum is σ = 152228201580. Its totient is φ = 27062791360.

The previous prime is 67656978427. The next prime is 67656978449. The reversal of 67656978440 is 4487965676.

It can be written as a sum of positive squares in 2 ways, for example, as 67509550276 + 147428164 = 259826^2 + 12142^2 .

It is not an unprimeable number, because it can be changed into a prime (67656978449) 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, 845712191 + ... + 845712270.

Almost surely, 2^67656978440 is an apocalyptic number.

It is an amenable number.

67656978440 is an abundant number, since it is smaller than the sum of its proper divisors (84571223140).

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

67656978440 is a wasteful number, since it uses less digits than its factorization.

67656978440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1691424472 (or 1691424468 counting only the distinct ones).

The product of its (nonzero) digits is 60963840, while the sum is 62.

The spelling of 67656978440 in words is "sixty-seven billion, six hundred fifty-six million, nine hundred seventy-eight thousand, four hundred forty".