1220516641 has 2 divisors, whose sum is σ = 1220516642. Its totient is φ = 1220516640.

The previous prime is 1220516639. The next prime is 1220516723. The reversal of 1220516641 is 1466150221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1219476241 + 1040400 = 34921^2 + 1020^2 .

It is an emirp because it is prime and its reverse (1466150221) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1220516641 - 2¹ = 1220516639 is a prime.

Together with 1220516639, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1220516611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 610258320 + 610258321.

It is an arithmetic number, because the mean of its divisors is an integer number (610258321).

Almost surely, 2^1220516641 is an apocalyptic number.

It is an amenable number.

1220516641 is a deficient number, since it is larger than the sum of its proper divisors (1).

1220516641 is an equidigital number, since it uses as much as digits as its factorization.

1220516641 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2880, while the sum is 28.

The square root of 1220516641 is about 34935.8933047375. The cubic root of 1220516641 is about 1068.6805411763.

Adding to 1220516641 its reverse (1466150221), we get a palindrome (2686666862).

The spelling of 1220516641 in words is "one billion, two hundred twenty million, five hundred sixteen thousand, six hundred forty-one".