155521103662091 has 2 divisors, whose sum is σ = 155521103662092. Its totient is φ = 155521103662090.

The previous prime is 155521103661991. The next prime is 155521103662121. The reversal of 155521103662091 is 190266301125551.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 155521103662091 - 2¹⁸ = 155521103399947 is a prime.

It is a super-2 number, since 2×155521103662091² (a number of 29 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (155521103662291) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77760551831045 + 77760551831046.

It is an arithmetic number, because the mean of its divisors is an integer number (77760551831046).

Almost surely, 2^{155521103662091} is an apocalyptic number.

155521103662091 is a deficient number, since it is larger than the sum of its proper divisors (1).

155521103662091 is an equidigital number, since it uses as much as digits as its factorization.

155521103662091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 486000, while the sum is 47.

The spelling of 155521103662091 in words is "one hundred fifty-five trillion, five hundred twenty-one billion, one hundred three million, six hundred sixty-two thousand, ninety-one".