155591869 has 4 divisors (see below), whose sum is σ = 155653596. Its totient is φ = 155530144.

The previous prime is 155591851. The next prime is 155591897. The reversal of 155591869 is 968195551.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 968195551 = 659 ⋅1469189.

It can be written as a sum of positive squares in 2 ways, for example, as 95296644 + 60295225 = 9762^2 + 7765^2 .

It is a cyclic number.

It is not a de Polignac number, because 155591869 - 2⁹ = 155591357 is a prime.

It is a super-2 number, since 2×155591869² = 48417659397826322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155591809) 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 3 ways as a sum of consecutive naturals, for example, 26914 + ... + 32179.

It is an arithmetic number, because the mean of its divisors is an integer number (38913399).

Almost surely, 2^155591869 is an apocalyptic number.

It is an amenable number.

155591869 is a deficient number, since it is larger than the sum of its proper divisors (61727).

155591869 is an equidigital number, since it uses as much as digits as its factorization.

155591869 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61726.

The product of its digits is 486000, while the sum is 49.

The square root of 155591869 is about 12473.6469807350. The cubic root of 155591869 is about 537.8513948127.

The spelling of 155591869 in words is "one hundred fifty-five million, five hundred ninety-one thousand, eight hundred sixty-nine".