681743790 has 192 divisors, whose sum is σ = 2263113216. Its totient is φ = 143793792.

The previous prime is 681743779. The next prime is 681743791. The reversal of 681743790 is 97347186.

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 (681743791) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 219589 + ... + 222671.

It is an arithmetic number, because the mean of its divisors is an integer number (11787048).

Almost surely, 2^681743790 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 681743790, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1131556608).

681743790 is an abundant number, since it is smaller than the sum of its proper divisors (1581369426).

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

681743790 is a wasteful number, since it uses less digits than its factorization.

681743790 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3125 (or 3113 counting only the distinct ones).

The product of its (nonzero) digits is 254016, while the sum is 45.

The square root of 681743790 is about 26110.2238596302. The cubic root of 681743790 is about 880.1169739478.

The spelling of 681743790 in words is "six hundred eighty-one million, seven hundred forty-three thousand, seven hundred ninety".