681183510818 has 4 divisors (see below), whose sum is σ = 1021775266230. Its totient is φ = 340591755408.

The previous prime is 681183510817. The next prime is 681183510827. The reversal of 681183510818 is 818015381186.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 543836927209 + 137346583609 = 737453^2 + 370603^2 .

It is not an unprimeable number, because it can be changed into a prime (681183510817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 170295877703 + ... + 170295877706.

Almost surely, 2^681183510818 is an apocalyptic number.

681183510818 is a deficient number, since it is larger than the sum of its proper divisors (340591755412).

681183510818 is a wasteful number, since it uses less digits than its factorization.

681183510818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 340591755411.

The product of its (nonzero) digits is 368640, while the sum is 50.

The spelling of 681183510818 in words is "six hundred eighty-one billion, one hundred eighty-three million, five hundred ten thousand, eight hundred eighteen".