1961680 has 80 divisors (see below), whose sum is σ = 5428224. Its totient is φ = 645120.

The previous prime is 1961671. The next prime is 1961683. The reversal of 1961680 is 861691.

It is a happy number.

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

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1961683) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 17304 + ... + 17416.

2^1961680 is an apocalyptic number.

1961680 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 1961680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2714112).

1961680 is an abundant number, since it is smaller than the sum of its proper divisors (3466544).

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

1961680 is a wasteful number, since it uses less digits than its factorization.

1961680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 164 (or 158 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 31.

The square root of 1961680 is about 1400.5998714836. The cubic root of 1961680 is about 125.1822408437.

The spelling of 1961680 in words is "one million, nine hundred sixty-one thousand, six hundred eighty".