155121172 has 6 divisors (see below), whose sum is σ = 271462058. Its totient is φ = 77560584.

The previous prime is 155121151. The next prime is 155121173. The reversal of 155121172 is 271121551.

It can be written as a sum of positive squares in only one way, i.e., 151683856 + 3437316 = 12316^2 + 1854^2 .

It is a super-3 number, since 3×155121172³ (a number of 26 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155121173) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19390143 + ... + 19390150.

Almost surely, 2^155121172 is an apocalyptic number.

It is an amenable number.

155121172 is a deficient number, since it is larger than the sum of its proper divisors (116340886).

155121172 is a wasteful number, since it uses less digits than its factorization.

155121172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38780297 (or 38780295 counting only the distinct ones).

The product of its digits is 700, while the sum is 25.

The square root of 155121172 is about 12454.7650319065. The cubic root of 155121172 is about 537.3084770681.

The spelling of 155121172 in words is "one hundred fifty-five million, one hundred twenty-one thousand, one hundred seventy-two".