2021256613646 has 16 divisors (see below), whose sum is σ = 3198011141760. Its totient is φ = 955471344120.

The previous prime is 2021256613583. The next prime is 2021256613763. The reversal of 2021256613646 is 6463166521202.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 2021256613597 and 2021256613606.

It is a congruent 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, 54592340 + ... + 54629351.

It is an arithmetic number, because the mean of its divisors is an integer number (199875696360).

Almost surely, 2^{2021256613646} is an apocalyptic number.

2021256613646 is a deficient number, since it is larger than the sum of its proper divisors (1176754528114).

2021256613646 is a wasteful number, since it uses less digits than its factorization.

2021256613646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 109222199.

The product of its (nonzero) digits is 622080, while the sum is 44.

The spelling of 2021256613646 in words is "two trillion, twenty-one billion, two hundred fifty-six million, six hundred thirteen thousand, six hundred forty-six".