155106105401221 has 8 divisors (see below), whose sum is σ = 176863070412504. Its totient is φ = 134752815552000.

The previous prime is 155106105401209. The next prime is 155106105401227. The reversal of 155106105401221 is 122104501601551.

It can be written as a sum of positive squares in 4 ways, for example, as 68825507500996 + 86280597900225 = 8296114^2 + 9288735^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 155106105401221 - 2⁵ = 155106105401189 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155106105401227) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 350918790280 + ... + 350918790721.

It is an arithmetic number, because the mean of its divisors is an integer number (22107883801563).

Almost surely, 2^{155106105401221} is an apocalyptic number.

It is an amenable number.

155106105401221 is a deficient number, since it is larger than the sum of its proper divisors (21756965011283).

155106105401221 is a wasteful number, since it uses less digits than its factorization.

155106105401221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 701837581031.

The product of its (nonzero) digits is 12000, while the sum is 34.

The spelling of 155106105401221 in words is "one hundred fifty-five trillion, one hundred six billion, one hundred five million, four hundred one thousand, two hundred twenty-one".