681109520 has 80 divisors (see below), whose sum is σ = 1949041920. Its totient is φ = 215557632.

The previous prime is 681109493. The next prime is 681109529. The reversal of 681109520 is 25901186.

It is a tau number, because it is divible by the number of its divisors (80).

It is not an unprimeable number, because it can be changed into a prime (681109529) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 39500 + ... + 54059.

It is an arithmetic number, because the mean of its divisors is an integer number (24363024).

Almost surely, 2^681109520 is an apocalyptic number.

It is an amenable number.

681109520 is an abundant number, since it is smaller than the sum of its proper divisors (1267932400).

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

681109520 is a wasteful number, since it uses less digits than its factorization.

681109520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93592 (or 93586 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 32.

The square root of 681109520 is about 26098.0750247983. The cubic root of 681109520 is about 879.8439461572.

The spelling of 681109520 in words is "six hundred eighty-one million, one hundred nine thousand, five hundred twenty".