2021556656 has 40 divisors (see below), whose sum is σ = 4509012000. Its totient is φ = 860050944.

The previous prime is 2021556617. The next prime is 2021556689. The reversal of 2021556656 is 6566551202.

It is a happy number.

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, 50531 + ... + 81218.

It is an arithmetic number, because the mean of its divisors is an integer number (112725300).

Almost surely, 2^2021556656 is an apocalyptic number.

It is an amenable number.

2021556656 is an abundant number, since it is smaller than the sum of its proper divisors (2487455344).

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

2021556656 is a wasteful number, since it uses less digits than its factorization.

2021556656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131901 (or 131895 counting only the distinct ones).

The product of its (nonzero) digits is 108000, while the sum is 38.

The square root of 2021556656 is about 44961.7243441574. The cubic root of 2021556656 is about 1264.4314975829.

The spelling of 2021556656 in words is "two billion, twenty-one million, five hundred fifty-six thousand, six hundred fifty-six".