155493281 has 4 divisors (see below), whose sum is σ = 155770032. Its totient is φ = 155216532.

The previous prime is 155493263. The next prime is 155493287. The reversal of 155493281 is 182394551.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-155493281 is a prime.

It is a super-2 number, since 2×155493281² = 48356320872289922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (155493287) by changing a digit.

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 in 3 ways as a sum of consecutive naturals, for example, 137531 + ... + 138656.

It is an arithmetic number, because the mean of its divisors is an integer number (38942508).

Almost surely, 2^155493281 is an apocalyptic number.

It is an amenable number.

155493281 is a deficient number, since it is larger than the sum of its proper divisors (276751).

155493281 is an equidigital number, since it uses as much as digits as its factorization.

155493281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 276750.

The product of its digits is 43200, while the sum is 38.

The square root of 155493281 is about 12469.6945030742. The cubic root of 155493281 is about 537.7377708442.

The spelling of 155493281 in words is "one hundred fifty-five million, four hundred ninety-three thousand, two hundred eighty-one".