6621220240 has 40 divisors (see below), whose sum is σ = 15397764480. Its totient is φ = 2647898496.

The previous prime is 6621220223. The next prime is 6621220253. The reversal of 6621220240 is 420221266.

It is a tau number, because it is divible by the number of its divisors (40).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 615387 + ... + 626053.

It is an arithmetic number, because the mean of its divisors is an integer number (384944112).

Almost surely, 2^6621220240 is an apocalyptic number.

It is an amenable number.

6621220240 is an abundant number, since it is smaller than the sum of its proper divisors (8776544240).

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

6621220240 is a wasteful number, since it uses less digits than its factorization.

6621220240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18439 (or 18433 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 25.

The square root of 6621220240 is about 81370.8807866795. The cubic root of 6621220240 is about 1877.7856303282.

The spelling of 6621220240 in words is "six billion, six hundred twenty-one million, two hundred twenty thousand, two hundred forty".