1965640 has 32 divisors (see below), whose sum is σ = 4465080. Its totient is φ = 778752.

The previous prime is 1965637. The next prime is 1965641. The reversal of 1965640 is 465691.

It can be written as a sum of positive squares in 4 ways, for example, as 715716 + 1249924 = 846^2 + 1118^2 .

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (1965641) 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 7 ways as a sum of consecutive naturals, for example, 6124 + ... + 6436.

2^1965640 is an apocalyptic number.

1965640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1965640 is an abundant number, since it is smaller than the sum of its proper divisors (2499440).

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

1965640 is a wasteful number, since it uses less digits than its factorization.

1965640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 481 (or 477 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 31.

The square root of 1965640 is about 1402.0128387429. The cubic root of 1965640 is about 125.2664184330.

The spelling of 1965640 in words is "one million, nine hundred sixty-five thousand, six hundred forty".