1221550756672 has 56 divisors (see below), whose sum is σ = 2662533460800. Its totient is φ = 553471497216.

The previous prime is 1221550756639. The next prime is 1221550756681. The reversal of 1221550756672 is 2766570551221.

It is a super-2 number, since 2×1221550756672² (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 7 ways as a sum of consecutive naturals, for example, 21810397 + ... + 21866332.

Almost surely, 2^{1221550756672} is an apocalyptic number.

It is an amenable number.

1221550756672 is an abundant number, since it is smaller than the sum of its proper divisors (1440982704128).

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

1221550756672 is a wasteful number, since it uses less digits than its factorization.

1221550756672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43676783 (or 43676773 counting only the distinct ones).

The product of its (nonzero) digits is 1764000, while the sum is 49.

The spelling of 1221550756672 in words is "one trillion, two hundred twenty-one billion, five hundred fifty million, seven hundred fifty-six thousand, six hundred seventy-two".