155121071 has 4 divisors (see below), whose sum is σ = 177281232. Its totient is φ = 132960912.

The previous prime is 155121059. The next prime is 155121079. The reversal of 155121071 is 170121551.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 170121551 = 6379 ⋅26669.

It is not a de Polignac number, because 155121071 - 2⁶ = 155121007 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 (155121079) 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 in 3 ways as a sum of consecutive naturals, for example, 11080070 + ... + 11080083.

It is an arithmetic number, because the mean of its divisors is an integer number (44320308).

Almost surely, 2^155121071 is an apocalyptic number.

155121071 is a deficient number, since it is larger than the sum of its proper divisors (22160161).

155121071 is an equidigital number, since it uses as much as digits as its factorization.

155121071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22160160.

The product of its (nonzero) digits is 350, while the sum is 23.

The square root of 155121071 is about 12454.7609772328. The cubic root of 155121071 is about 537.3083604535.

It can be divided in two parts, 1551 and 21071, that added together give a palindrome (22622).

The spelling of 155121071 in words is "one hundred fifty-five million, one hundred twenty-one thousand, seventy-one".