155213028 has 18 divisors (see below), whose sum is σ = 392344134. Its totient is φ = 51737664.

The previous prime is 155213021. The next prime is 155213081. The reversal of 155213028 is 820312551.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 135070884 + 20142144 = 11622^2 + 4488^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a junction number, because it is equal to n+sod(n) for n = 155212992 and 155213010.

It is not an unprimeable number, because it can be changed into a prime (155213021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2155701 + ... + 2155772.

Almost surely, 2^155213028 is an apocalyptic number.

155213028 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

155213028 is an abundant number, since it is smaller than the sum of its proper divisors (237131106).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

155213028 is a wasteful number, since it uses less digits than its factorization.

155213028 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4311483 (or 4311478 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 27.

The square root of 155213028 is about 12458.4520707831. The cubic root of 155213028 is about 537.4145130314.

Adding to 155213028 its reverse (820312551), we get a palindrome (975525579).

The spelling of 155213028 in words is "one hundred fifty-five million, two hundred thirteen thousand, twenty-eight".