681798240 has 72 divisors (see below), whose sum is σ = 2326641408. Its totient is φ = 181812480.

The previous prime is 681798179. The next prime is 681798241. The reversal of 681798240 is 42897186.

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681798241) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 235296 + ... + 238175.

It is an arithmetic number, because the mean of its divisors is an integer number (32314464).

Almost surely, 2^681798240 is an apocalyptic number.

681798240 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

681798240 is an abundant number, since it is smaller than the sum of its proper divisors (1644843168).

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

681798240 is a wasteful number, since it uses less digits than its factorization.

681798240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 473492 (or 473481 counting only the distinct ones).

The product of its (nonzero) digits is 193536, while the sum is 45.

The square root of 681798240 is about 26111.2665338164. The cubic root of 681798240 is about 880.1404045944.

The spelling of 681798240 in words is "six hundred eighty-one million, seven hundred ninety-eight thousand, two hundred forty".