681488747540 has 48 divisors (see below), whose sum is σ = 1449042959952. Its totient is φ = 269203439616.

The previous prime is 681488747539. The next prime is 681488747551. The reversal of 681488747540 is 45747884186.

It can be written as a sum of positive squares in 8 ways, for example, as 175381713796 + 506107033744 = 418786^2 + 711412^2 .

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 115529 + ... + 1173168.

It is an arithmetic number, because the mean of its divisors is an integer number (30188394999).

Almost surely, 2^681488747540 is an apocalyptic number.

It is an amenable number.

681488747540 is an abundant number, since it is smaller than the sum of its proper divisors (767554212412).

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

681488747540 is a wasteful number, since it uses less digits than its factorization.

681488747540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1289036 (or 1289034 counting only the distinct ones).

The product of its (nonzero) digits is 48168960, while the sum is 62.

The spelling of 681488747540 in words is "six hundred eighty-one billion, four hundred eighty-eight million, seven hundred forty-seven thousand, five hundred forty".