22165631577781 has 2 divisors, whose sum is σ = 22165631577782. Its totient is φ = 22165631577780.

The previous prime is 22165631577773. The next prime is 22165631577809. The reversal of 22165631577781 is 18777513656122.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12015991355281 + 10149640222500 = 3466409^2 + 3185850^2 .

It is a cyclic number.

It is not a de Polignac number, because 22165631577781 - 2³ = 22165631577773 is a prime.

It is a super-2 number, since 2×22165631577781² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22165631572781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11082815788890 + 11082815788891.

It is an arithmetic number, because the mean of its divisors is an integer number (11082815788891).

Almost surely, 2^{22165631577781} is an apocalyptic number.

It is an amenable number.

22165631577781 is a deficient number, since it is larger than the sum of its proper divisors (1).

22165631577781 is an equidigital number, since it uses as much as digits as its factorization.

22165631577781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 29635200, while the sum is 61.

The spelling of 22165631577781 in words is "twenty-two trillion, one hundred sixty-five billion, six hundred thirty-one million, five hundred seventy-seven thousand, seven hundred eighty-one".