6651940 has 24 divisors (see below), whose sum is σ = 14023800. Its totient is φ = 2650368.

The previous prime is 6651923. The next prime is 6651941. The reversal of 6651940 is 491566.

It can be written as a sum of positive squares in 4 ways, for example, as 1016064 + 5635876 = 1008^2 + 2374^2 .

It is not an unprimeable number, because it can be changed into a prime (6651941) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6504 + ... + 7456.

It is an arithmetic number, because the mean of its divisors is an integer number (584325).

Almost surely, 2^6651940 is an apocalyptic number.

It is an amenable number.

6651940 is an abundant number, since it is smaller than the sum of its proper divisors (7371860).

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

6651940 is a wasteful number, since it uses less digits than its factorization.

6651940 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1311 (or 1309 counting only the distinct ones).

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

The square root of 6651940 is about 2579.1355140822. The cubic root of 6651940 is about 188.0685203681.

The spelling of 6651940 in words is "six million, six hundred fifty-one thousand, nine hundred forty".