155272666 has 4 divisors (see below), whose sum is σ = 232909002. Its totient is φ = 77636332.

The previous prime is 155272661. The next prime is 155272681. The reversal of 155272666 is 666272551.

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., 97436641 + 57836025 = 9871^2 + 7605^2 .

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (155272661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38818165 + ... + 38818168.

Almost surely, 2^155272666 is an apocalyptic number.

155272666 is a deficient number, since it is larger than the sum of its proper divisors (77636336).

155272666 is an equidigital number, since it uses as much as digits as its factorization.

155272666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77636335.

The product of its digits is 151200, while the sum is 40.

The square root of 155272666 is about 12460.8453164302. The cubic root of 155272666 is about 537.4833350521.

The spelling of 155272666 in words is "one hundred fifty-five million, two hundred seventy-two thousand, six hundred sixty-six".