1227616969921 has 2 divisors, whose sum is σ = 1227616969922. Its totient is φ = 1227616969920.

The previous prime is 1227616969913. The next prime is 1227616969939. The reversal of 1227616969921 is 1299696167221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1220938811521 + 6678158400 = 1104961^2 + 81720^2 .

It is an emirp because it is prime and its reverse (1299696167221) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1227616969921 - 2³ = 1227616969913 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1227616969921.

It is not a weakly prime, because it can be changed into another prime (1227616969961) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 613808484960 + 613808484961.

It is an arithmetic number, because the mean of its divisors is an integer number (613808484961).

Almost surely, 2^{1227616969921} is an apocalyptic number.

It is an amenable number.

1227616969921 is a deficient number, since it is larger than the sum of its proper divisors (1).

1227616969921 is an equidigital number, since it uses as much as digits as its factorization.

1227616969921 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8817984, while the sum is 61.

The spelling of 1227616969921 in words is "one trillion, two hundred twenty-seven billion, six hundred sixteen million, nine hundred sixty-nine thousand, nine hundred twenty-one".