1221617351824 has 45 divisors (see below), whose sum is σ = 2498184684723. Its totient is φ = 578621061216.

The previous prime is 1221617351813. The next prime is 1221617351827. The reversal of 1221617351824 is 4281537161221.

The square root of 1221617351824 is 1105268.

It is a perfect power (a square), and thus also a powerful number.

It is a super-2 number, since 2×1221617351824² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221617351827) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 83993097 + ... + 84007639.

Almost surely, 2^{1221617351824} is an apocalyptic number.

1221617351824 is the 1105268-th square number.

It is an amenable number.

1221617351824 is an abundant number, since it is smaller than the sum of its proper divisors (1276567332899).

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

1221617351824 is an frugal number, since it uses more digits than its factorization.

1221617351824 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29132 (or 14564 counting only the distinct ones).

The product of its digits is 161280, while the sum is 43.

The spelling of 1221617351824 in words is "one trillion, two hundred twenty-one billion, six hundred seventeen million, three hundred fifty-one thousand, eight hundred twenty-four".