155112311251421 has 2 divisors, whose sum is σ = 155112311251422. Its totient is φ = 155112311251420.

The previous prime is 155112311251379. The next prime is 155112311251427. The reversal of 155112311251421 is 124152113211551.

155112311251421 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 83335172016100 + 71777139235321 = 9128810^2 + 8472139^2 .

It is a cyclic number.

It is not a de Polignac number, because 155112311251421 - 2¹⁸ = 155112310989277 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (155112311251427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77556155625710 + 77556155625711.

It is an arithmetic number, because the mean of its divisors is an integer number (77556155625711).

Almost surely, 2^{155112311251421} is an apocalyptic number.

It is an amenable number.

155112311251421 is a deficient number, since it is larger than the sum of its proper divisors (1).

155112311251421 is an equidigital number, since it uses as much as digits as its factorization.

155112311251421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12000, while the sum is 35.

Adding to 155112311251421 its reverse (124152113211551), we get a palindrome (279264424462972).

The spelling of 155112311251421 in words is "one hundred fifty-five trillion, one hundred twelve billion, three hundred eleven million, two hundred fifty-one thousand, four hundred twenty-one".