155515138 has 4 divisors (see below), whose sum is σ = 233272710. Its totient is φ = 77757568.

The previous prime is 155515103. The next prime is 155515141. The reversal of 155515138 is 831515551.

It is a happy number.

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

It can be written as a sum of positive squares in only one way, i.e., 110397049 + 45118089 = 10507^2 + 6717^2 .

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 38878783 + ... + 38878786.

Almost surely, 2^155515138 is an apocalyptic number.

155515138 is a deficient number, since it is larger than the sum of its proper divisors (77757572).

155515138 is an equidigital number, since it uses as much as digits as its factorization.

155515138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77757571.

The product of its digits is 15000, while the sum is 34.

The square root of 155515138 is about 12470.5708770689. The cubic root of 155515138 is about 537.7629654673.

The spelling of 155515138 in words is "one hundred fifty-five million, five hundred fifteen thousand, one hundred thirty-eight".