155377221 has 8 divisors (see below), whose sum is σ = 210261984. Its totient is φ = 102038640.

The previous prime is 155377169. The next prime is 155377237. The reversal of 155377221 is 122773551.

It is a happy number.

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

It is not a de Polignac number, because 155377221 - 2¹⁷ = 155246149 is a prime.

It is a super-3 number, since 3×155377221³ (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 (155377721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 386310 + ... + 386711.

It is an arithmetic number, because the mean of its divisors is an integer number (26282748).

Almost surely, 2^155377221 is an apocalyptic number.

It is an amenable number.

155377221 is a deficient number, since it is larger than the sum of its proper divisors (54884763).

155377221 is an equidigital number, since it uses as much as digits as its factorization.

155377221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 773091.

The product of its digits is 14700, while the sum is 33.

The square root of 155377221 is about 12465.0399518012. The cubic root of 155377221 is about 537.6039485996.

The spelling of 155377221 in words is "one hundred fifty-five million, three hundred seventy-seven thousand, two hundred twenty-one".