681353678525 has 24 divisors (see below), whose sum is σ = 918877870344. Its totient is φ = 498171744000.

The previous prime is 681353678513. The next prime is 681353678531. The reversal of 681353678525 is 525876353186.

It can be written as a sum of positive squares in 12 ways, for example, as 167061030361 + 514292648164 = 408731^2 + 717142^2 .

It is not a de Polignac number, because 681353678525 - 2³⁰ = 680279936701 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 10345754 + ... + 10411403.

It is an arithmetic number, because the mean of its divisors is an integer number (38286577931).

Almost surely, 2^681353678525 is an apocalyptic number.

681353678525 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

681353678525 is a deficient number, since it is larger than the sum of its proper divisors (237524191819).

681353678525 is a wasteful number, since it uses less digits than its factorization.

681353678525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20757281 (or 20757276 counting only the distinct ones).

The product of its digits is 36288000, while the sum is 59.

The spelling of 681353678525 in words is "six hundred eighty-one billion, three hundred fifty-three million, six hundred seventy-eight thousand, five hundred twenty-five".