11550157776221 has 2 divisors, whose sum is σ = 11550157776222. Its totient is φ = 11550157776220.

The previous prime is 11550157776187. The next prime is 11550157776253. The reversal of 11550157776221 is 12267775105511.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9806730664900 + 1743427111321 = 3131570^2 + 1320389^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11550157776221 is a prime.

It is a super-2 number, since 2×11550157776221² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 11550157776221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (11550157776281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5775078888110 + 5775078888111.

It is an arithmetic number, because the mean of its divisors is an integer number (5775078888111).

Almost surely, 2^{11550157776221} is an apocalyptic number.

It is an amenable number.

11550157776221 is a deficient number, since it is larger than the sum of its proper divisors (1).

11550157776221 is an equidigital number, since it uses as much as digits as its factorization.

11550157776221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1029000, while the sum is 50.

The spelling of 11550157776221 in words is "eleven trillion, five hundred fifty billion, one hundred fifty-seven million, seven hundred seventy-six thousand, two hundred twenty-one".