155506066 has 4 divisors (see below), whose sum is σ = 233259102. Its totient is φ = 77753032.

The previous prime is 155506063. The next prime is 155506121. The reversal of 155506066 is 660605551.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 660605551 = 1039 ⋅635809.

It can be written as a sum of positive squares in only one way, i.e., 101909025 + 53597041 = 10095^2 + 7321^2 .

It is not an unprimeable number, because it can be changed into a prime (155506063) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38876515 + ... + 38876518.

Almost surely, 2^155506066 is an apocalyptic number.

155506066 is a deficient number, since it is larger than the sum of its proper divisors (77753036).

155506066 is an equidigital number, since it uses as much as digits as its factorization.

155506066 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77753035.

The product of its (nonzero) digits is 27000, while the sum is 34.

The square root of 155506066 is about 12470.2071354088. The cubic root of 155506066 is about 537.7525084349.

The spelling of 155506066 in words is "one hundred fifty-five million, five hundred six thousand, sixty-six".