1211221307984 has 20 divisors (see below), whose sum is σ = 2346766958016. Its totient is φ = 605604028512.

The previous prime is 1211221307963. The next prime is 1211221307993. The reversal of 1211221307984 is 4897031221121.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1312187 + ... + 2035749.

Almost surely, 2^{1211221307984} is an apocalyptic number.

It is an amenable number.

1211221307984 is a deficient number, since it is larger than the sum of its proper divisors (1135545650032).

1211221307984 is a wasteful number, since it uses less digits than its factorization.

1211221307984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 828194 (or 828188 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 41.

Adding to 1211221307984 its sum of digits (41), we get a square (1211221308025 = 1100555²).

The spelling of 1211221307984 in words is "one trillion, two hundred eleven billion, two hundred twenty-one million, three hundred seven thousand, nine hundred eighty-four".