1000021666556 has 48 divisors (see below), whose sum is σ = 1914622950240. Its totient is φ = 453249408000.

The previous prime is 1000021666537. The next prime is 1000021666573. The reversal of 1000021666556 is 6556661200001.

It is a super-2 number, since 2×1000021666556² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 30023960 + ... + 30057248.

It is an arithmetic number, because the mean of its divisors is an integer number (39887978130).

Almost surely, 2^{1000021666556} is an apocalyptic number.

It is an amenable number.

1000021666556 is a deficient number, since it is larger than the sum of its proper divisors (914601283684).

1000021666556 is a wasteful number, since it uses less digits than its factorization.

1000021666556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35246 (or 35244 counting only the distinct ones).

The product of its (nonzero) digits is 64800, while the sum is 38.

Adding to 1000021666556 its reverse (6556661200001), we get a palindrome (7556682866557).

The spelling of 1000021666556 in words is "one trillion, twenty-one million, six hundred sixty-six thousand, five hundred fifty-six".