681734144 has 208 divisors, whose sum is σ = 1761392640. Its totient is φ = 256573440.

The previous prime is 681734111. The next prime is 681734149. The reversal of 681734144 is 441437186.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (208).

It is a super-2 number, since 2×681734144² = 929522886190825472, which contains 22 as substring.

Its product of digits (64512) is a multiple of the sum of its prime divisors (112).

It is a junction number, because it is equal to n+sod(n) for n = 681734098 and 681734107.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (681734149) 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, 11554787 + ... + 11554845.

Almost surely, 2^681734144 is an apocalyptic number.

681734144 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 681734144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (880696320).

681734144 is an abundant number, since it is smaller than the sum of its proper divisors (1079658496).

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

681734144 is a wasteful number, since it uses less digits than its factorization.

681734144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134 (or 112 counting only the distinct ones).

The product of its digits is 64512, while the sum is 38.

The square root of 681734144 is about 26110.0391420618. The cubic root of 681734144 is about 880.1128230001.

The spelling of 681734144 in words is "six hundred eighty-one million, seven hundred thirty-four thousand, one hundred forty-four".