155165875113721 has 4 divisors (see below), whose sum is σ = 155170583277732. Its totient is φ = 155161166949712.

The previous prime is 155165875113649. The next prime is 155165875113749. The reversal of 155165875113721 is 127311578561551.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 152578425925696 + 2587449188025 = 12352264^2 + 1608555^2 .

It is a cyclic number.

It is not a de Polignac number, because 155165875113721 - 2³¹ = 155163727630073 is a prime.

It is a Smith number, since the sum of its digits (58) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (155165875113761) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2354032570 + ... + 2354098483.

It is an arithmetic number, because the mean of its divisors is an integer number (38792645819433).

Almost surely, 2^{155165875113721} is an apocalyptic number.

It is an amenable number.

155165875113721 is a deficient number, since it is larger than the sum of its proper divisors (4708164011).

155165875113721 is an equidigital number, since it uses as much as digits as its factorization.

155165875113721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4708164010.

The product of its digits is 8820000, while the sum is 58.

The spelling of 155165875113721 in words is "one hundred fifty-five trillion, one hundred sixty-five billion, eight hundred seventy-five million, one hundred thirteen thousand, seven hundred twenty-one".