155638978 has 16 divisors (see below), whose sum is σ = 269663904. Its totient is φ = 66583360.

The previous prime is 155638939. The next prime is 155638979. The reversal of 155638978 is 879836551.

It is not an unprimeable number, because it can be changed into a prime (155638979) 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, 207700 + ... + 208447.

It is an arithmetic number, because the mean of its divisors is an integer number (16853994).

Almost surely, 2^155638978 is an apocalyptic number.

155638978 is a deficient number, since it is larger than the sum of its proper divisors (114024926).

155638978 is a wasteful number, since it uses less digits than its factorization.

155638978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 416177.

The product of its digits is 1814400, while the sum is 52.

The square root of 155638978 is about 12475.5351789011. The cubic root of 155638978 is about 537.9056716092.

The spelling of 155638978 in words is "one hundred fifty-five million, six hundred thirty-eight thousand, nine hundred seventy-eight".