1681255840 has 192 divisors, whose sum is σ = 4636300032. Its totient is φ = 569958400.

The previous prime is 1681255819. The next prime is 1681255843. The reversal of 1681255840 is 485521861.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 1681255793 and 1681255802.

It is not an unprimeable number, because it can be changed into a prime (1681255843) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1659174 + ... + 1660186.

It is an arithmetic number, because the mean of its divisors is an integer number (24147396).

Almost surely, 2^1681255840 is an apocalyptic number.

1681255840 is a gapful number since it is divisible by the number (10) 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 1681255840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2318150016).

1681255840 is an abundant number, since it is smaller than the sum of its proper divisors (2955044192).

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

1681255840 is a wasteful number, since it uses less digits than its factorization.

1681255840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1103 (or 1095 counting only the distinct ones).

The product of its (nonzero) digits is 76800, while the sum is 40.

The square root of 1681255840 is about 41003.1198812968. The cubic root of 1681255840 is about 1189.0805316528.

The spelling of 1681255840 in words is "one billion, six hundred eighty-one million, two hundred fifty-five thousand, eight hundred forty".