1227521641 has 2 divisors, whose sum is σ = 1227521642. Its totient is φ = 1227521640.

The previous prime is 1227521639. The next prime is 1227521699. The reversal of 1227521641 is 1461257221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 912281616 + 315240025 = 30204^2 + 17755^2 .

It is an emirp because it is prime and its reverse (1461257221) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1227521641 - 2¹ = 1227521639 is a prime.

Together with 1227521639, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1227521621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 613760820 + 613760821.

It is an arithmetic number, because the mean of its divisors is an integer number (613760821).

Almost surely, 2^1227521641 is an apocalyptic number.

It is an amenable number.

1227521641 is a deficient number, since it is larger than the sum of its proper divisors (1).

1227521641 is an equidigital number, since it uses as much as digits as its factorization.

1227521641 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6720, while the sum is 31.

The square root of 1227521641 is about 35036.0049235069. The cubic root of 1227521641 is about 1070.7211608556.

Adding to 1227521641 its reverse (1461257221), we get a palindrome (2688778862).

The spelling of 1227521641 in words is "one billion, two hundred twenty-seven million, five hundred twenty-one thousand, six hundred forty-one".