1221782116 has 9 divisors (see below), whose sum is σ = 2138241049. Its totient is φ = 610856104.

The previous prime is 1221782113. The next prime is 1221782119. The reversal of 1221782116 is 6112871221.

The square root of 1221782116 is 34954.

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

It is an interprime number because it is at equal distance from previous prime (1221782113) and next prime (1221782119).

It can be written as a sum of positive squares in only one way, i.e., 99800100 + 1121982016 = 9990^2 + 33496^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221782113) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 61170 + ... + 78646.

Almost surely, 2^1221782116 is an apocalyptic number.

1221782116 is the 34954-th square number.

It is an amenable number.

1221782116 is a deficient number, since it is larger than the sum of its proper divisors (916458933).

1221782116 is an frugal number, since it uses more digits than its factorization.

1221782116 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34958 (or 17479 counting only the distinct ones).

The product of its digits is 2688, while the sum is 31.

The cubic root of 1221782116 is about 1069.0497622450.

The spelling of 1221782116 in words is "one billion, two hundred twenty-one million, seven hundred eighty-two thousand, one hundred sixteen".