155420138 has 8 divisors (see below), whose sum is σ = 234351360. Its totient is φ = 77303020.

The previous prime is 155420129. The next prime is 155420141. The reversal of 155420138 is 831024551.

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

It is a self number, because there is not a number n which added to its sum of digits gives 155420138.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 203048 + ... + 203811.

It is an arithmetic number, because the mean of its divisors is an integer number (29293920).

Almost surely, 2^155420138 is an apocalyptic number.

155420138 is a deficient number, since it is larger than the sum of its proper divisors (78931222).

155420138 is a wasteful number, since it uses less digits than its factorization.

155420138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 407052.

The product of its (nonzero) digits is 4800, while the sum is 29.

The square root of 155420138 is about 12466.7613276264. The cubic root of 155420138 is about 537.6534415359.

Adding to 155420138 its reverse (831024551), we get a palindrome (986444689).

The spelling of 155420138 in words is "one hundred fifty-five million, four hundred twenty thousand, one hundred thirty-eight".