68451993650 has 24 divisors (see below), whose sum is σ = 129722990724. Its totient is φ = 26864177600.

The previous prime is 68451993641. The next prime is 68451993679. The reversal of 68451993650 is 5639915486.

It can be written as a sum of positive squares in 6 ways, for example, as 22179251329 + 46272742321 = 148927^2 + 215111^2 .

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 12912821 + ... + 12918120.

Almost surely, 2^68451993650 is an apocalyptic number.

68451993650 is a deficient number, since it is larger than the sum of its proper divisors (61270997074).

68451993650 is a wasteful number, since it uses less digits than its factorization.

68451993650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25831006 (or 25831001 counting only the distinct ones).

The product of its (nonzero) digits is 6998400, while the sum is 56.

The spelling of 68451993650 in words is "sixty-eight billion, four hundred fifty-one million, nine hundred ninety-three thousand, six hundred fifty".