6661940 has 12 divisors (see below), whose sum is σ = 13990116. Its totient is φ = 2664768.

The previous prime is 6661933. The next prime is 6661957. The reversal of 6661940 is 491666.

It can be written as a sum of positive squares in 2 ways, for example, as 4477456 + 2184484 = 2116^2 + 1478^2 .

It is a hoax number, since the sum of its digits (32) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 6661897 and 6661906.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 166529 + ... + 166568.

It is an arithmetic number, because the mean of its divisors is an integer number (1165843).

Almost surely, 2^6661940 is an apocalyptic number.

It is an amenable number.

6661940 is an abundant number, since it is smaller than the sum of its proper divisors (7328176).

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

6661940 is a wasteful number, since it uses less digits than its factorization.

6661940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333106 (or 333104 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 32.

The square root of 6661940 is about 2581.0734201103. The cubic root of 6661940 is about 188.1627156237.

The spelling of 6661940 in words is "six million, six hundred sixty-one thousand, nine hundred forty".